< draft-ietf-ippm-ioam-data-09.txt   draft-ietf-ippm-ioam-data-10.txt >
ippm F. Brockners ippm F. Brockners, Ed.
Internet-Draft S. Bhandari Internet-Draft S. Bhandari, Ed.
Intended status: Standards Track C. Pignataro Intended status: Standards Track Cisco
Expires: September 9, 2020 Cisco Expires: January 14, 2021 T. Mizrahi, Ed.
H. Gredler Huawei
RtBrick Inc. July 13, 2020
J. Leddy
S. Youell
JPMC
T. Mizrahi
Huawei Network.IO Innovation Lab
D. Mozes
P. Lapukhov
Facebook
R. Chang
Barefoot Networks
D. Bernier
Bell Canada
J. Lemon
Broadcom
March 08, 2020
Data Fields for In-situ OAM Data Fields for In-situ OAM
draft-ietf-ippm-ioam-data-09 draft-ietf-ippm-ioam-data-10
Abstract Abstract
In-situ Operations, Administration, and Maintenance (IOAM) records In-situ Operations, Administration, and Maintenance (IOAM) records
operational and telemetry information in the packet while the packet operational and telemetry information in the packet while the packet
traverses a path between two points in the network. This document traverses a path between two points in the network. This document
discusses the data fields and associated data types for in-situ OAM. discusses the data fields and associated data types for in-situ OAM.
In-situ OAM data fields can be encapsulated into a variety of In-situ OAM data fields can be encapsulated into a variety of
protocols such as NSH, Segment Routing, Geneve, IPv6 (via extension protocols such as NSH, Segment Routing, Geneve, IPv6 (via extension
header), or IPv4. In-situ OAM can be used to complement OAM header), or IPv4. In-situ OAM can be used to complement OAM
skipping to change at page 2, line 10 skipping to change at page 1, line 39
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on September 9, 2020. This Internet-Draft will expire on January 14, 2021.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Scope, Applicability, and Assumptions . . . . . . . . . . . . 4 3. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. IOAM Data-Fields, Types, Nodes . . . . . . . . . . . . . . . 6 4. Scope, Applicability, and Assumptions . . . . . . . . . . . . 5
4.1. IOAM Data-Fields and Option-Types . . . . . . . . . . . . 6 5. IOAM Data-Fields, Types, Nodes . . . . . . . . . . . . . . . 6
4.2. IOAM-Domains and types of IOAM Nodes . . . . . . . . . . 6 5.1. IOAM Data-Fields and Option-Types . . . . . . . . . . . . 6
4.3. IOAM-Namespaces . . . . . . . . . . . . . . . . . . . . . 8 5.2. IOAM-Domains and types of IOAM Nodes . . . . . . . . . . 7
4.4. IOAM Trace Option-Types . . . . . . . . . . . . . . . . . 10 5.3. IOAM-Namespaces . . . . . . . . . . . . . . . . . . . . . 8
4.4.1. Pre-allocated and Incremental Trace Option-Types . . 12 5.4. IOAM Trace Option-Types . . . . . . . . . . . . . . . . . 10
4.4.2. IOAM node data fields and associated formats . . . . 16 5.4.1. Pre-allocated and Incremental Trace Option-Types . . 13
4.4.3. Examples of IOAM node data . . . . . . . . . . . . . 22 5.4.2. IOAM node data fields and associated formats . . . . 17
4.5. IOAM Proof of Transit Option-Type . . . . . . . . . . . . 24 5.4.2.1. Hop_Lim and node_id short format . . . . . . . . 17
4.5.1. IOAM Proof of Transit Type 0 . . . . . . . . . . . . 26 5.4.2.2. ingress_if_id and egress_if_id . . . . . . . . . 18
4.6. IOAM Edge-to-Edge Option-Type . . . . . . . . . . . . . . 27 5.4.2.3. timestamp seconds . . . . . . . . . . . . . . . . 18
5. Timestamp Formats . . . . . . . . . . . . . . . . . . . . . . 29 5.4.2.4. timestamp subseconds . . . . . . . . . . . . . . 18
5.1. PTP Truncated Timestamp Format . . . . . . . . . . . . . 29 5.4.2.5. transit delay . . . . . . . . . . . . . . . . . . 19
5.2. NTP 64-bit Timestamp Format . . . . . . . . . . . . . . . 30 5.4.2.6. namespace specific data . . . . . . . . . . . . . 19
5.3. POSIX-based Timestamp Format . . . . . . . . . . . . . . 32 5.4.2.7. queue depth . . . . . . . . . . . . . . . . . . . 19
6. IOAM Data Export . . . . . . . . . . . . . . . . . . . . . . 33 5.4.2.8. Checksum Complement . . . . . . . . . . . . . . . 20
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 33 5.4.2.9. Hop_Lim and node_id wide . . . . . . . . . . . . 20
7.1. Creation of a new In-Situ OAM Protocol Parameters 5.4.2.10. ingress_if_id and egress_if_id wide . . . . . . . 21
Registry (IOAM) Protocol Parameters IANA registry . . . . 33 5.4.2.11. namespace specific data wide . . . . . . . . . . 21
7.2. IOAM Option-Type Registry . . . . . . . . . . . . . . . . 34 5.4.2.12. buffer occupancy . . . . . . . . . . . . . . . . 22
7.3. IOAM Trace-Type Registry . . . . . . . . . . . . . . . . 34 5.4.2.13. Opaque State Snapshot . . . . . . . . . . . . . . 22
7.4. IOAM Trace-Flags Registry . . . . . . . . . . . . . . . . 35 5.4.3. Examples of IOAM node data . . . . . . . . . . . . . 23
7.5. IOAM POT-Type Registry . . . . . . . . . . . . . . . . . 35 5.5. IOAM Proof of Transit Option-Type . . . . . . . . . . . . 25
7.6. IOAM POT-Flags Registry . . . . . . . . . . . . . . . . . 36 5.5.1. IOAM Proof of Transit Type 0 . . . . . . . . . . . . 27
7.7. IOAM E2E-Type Registry . . . . . . . . . . . . . . . . . 36 5.6. IOAM Edge-to-Edge Option-Type . . . . . . . . . . . . . . 28
7.8. IOAM Namespace-ID Registry . . . . . . . . . . . . . . . 36 6. Timestamp Formats . . . . . . . . . . . . . . . . . . . . . . 30
8. Security Considerations . . . . . . . . . . . . . . . . . . . 37 6.1. PTP Truncated Timestamp Format . . . . . . . . . . . . . 30
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 38 6.2. NTP 64-bit Timestamp Format . . . . . . . . . . . . . . . 31
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 38 6.3. POSIX-based Timestamp Format . . . . . . . . . . . . . . 33
10.1. Normative References . . . . . . . . . . . . . . . . . . 39 7. IOAM Data Export . . . . . . . . . . . . . . . . . . . . . . 34
10.2. Informative References . . . . . . . . . . . . . . . . . 39 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 34
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 41 8.1. IOAM Option-Type Registry . . . . . . . . . . . . . . . . 35
8.2. IOAM Trace-Type Registry . . . . . . . . . . . . . . . . 35
8.3. IOAM Trace-Flags Registry . . . . . . . . . . . . . . . . 36
8.4. IOAM POT-Type Registry . . . . . . . . . . . . . . . . . 36
8.5. IOAM POT-Flags Registry . . . . . . . . . . . . . . . . . 36
8.6. IOAM E2E-Type Registry . . . . . . . . . . . . . . . . . 37
8.7. IOAM Namespace-ID Registry . . . . . . . . . . . . . . . 37
9. Management and Deployment Considerations . . . . . . . . . . 38
10. Security Considerations . . . . . . . . . . . . . . . . . . . 38
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 39
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 40
12.1. Normative References . . . . . . . . . . . . . . . . . . 40
12.2. Informative References . . . . . . . . . . . . . . . . . 40
Contributors' Addresses . . . . . . . . . . . . . . . . . . . . . 42
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 44
1. Introduction 1. Introduction
This document defines data fields for "in-situ" Operations, This document defines data fields for "in-situ" Operations,
Administration, and Maintenance (IOAM). In-situ OAM records OAM Administration, and Maintenance (IOAM). In-situ OAM records OAM
information within the packet while the packet traverses a particular information within the packet while the packet traverses a particular
network domain. The term "in-situ" refers to the fact that the OAM network domain. The term "in-situ" refers to the fact that the OAM
data is added to the data packets rather than is being sent within data is added to the data packets rather than being sent within
packets specifically dedicated to OAM. IOAM is to complement packets specifically dedicated to OAM. IOAM is to complement
mechanisms such as Ping or Traceroute. In terms of "active" or mechanisms such as Ping or Traceroute. In terms of "active" or
"passive" OAM, "in-situ" OAM can be considered a hybrid OAM type. "passive" OAM, "in-situ" OAM can be considered a hybrid OAM type.
"In-situ" mechanisms do not require extra packets to be sent. IOAM "In-situ" mechanisms do not require extra packets to be sent. IOAM
adds information to the already available data packets and therefore adds information to the already available data packets and therefore
cannot be considered passive. In terms of the classification given cannot be considered passive. In terms of the classification given
in [RFC7799] IOAM could be portrayed as Hybrid Type 1. IOAM in [RFC7799] IOAM could be portrayed as Hybrid Type 1. IOAM
mechanisms can be leveraged where mechanisms using e.g. ICMP do not mechanisms can be leveraged where mechanisms using e.g. ICMP do not
apply or do not offer the desired results, such as proving that a apply or do not offer the desired results, such as proving that a
certain traffic flow takes a pre-defined path, SLA verification for certain traffic flow takes a pre-defined path, SLA verification for
the live data traffic, detailed statistics on traffic distribution the live data traffic, detailed statistics on traffic distribution
paths in networks that distribute traffic across multiple paths, or paths in networks that distribute traffic across multiple paths, or
scenarios in which probe traffic is potentially handled differently scenarios in which probe traffic is potentially handled differently
from regular data traffic by the network devices. from regular data traffic by the network devices.
IOAM use cases and mechanisms have expanded as this document matured, IOAM use cases and mechanisms have expanded as this document matured,
resulting in additional flags and options that may trigger creation resulting in additional flags and options that could trigger creation
of additional packets dedicated to OAM. The term IOAM continues to of additional packets dedicated to OAM. The term IOAM continues to
be used for such mechanisms, in addition to the "in-situ" mechanisms be used for such mechanisms, in addition to the "in-situ" mechanisms
that motivated this terminology. that motivated this terminology.
2. Conventions 2. Contributors
This document was the collective effort of several authors. The text
and content were contributed by the editors and the co-authors listed
below. The contact information of the co-authors appears at the end
of this document.
o Carlos Pignataro
o Mickey Spiegel
o Barak Gafni
o Jennifer Lemon
o Hannes Gredler
o John Leddy
o Stephen Youell
o David Mozes
o Petr Lapukhov
o Remy Chang
o Daniel Bernier
3. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
Abbreviations used in this document: Abbreviations used in this document:
E2E Edge to Edge E2E Edge to Edge
Geneve: Generic Network Virtualization Encapsulation Geneve: Generic Network Virtualization Encapsulation
[I-D.ietf-nvo3-geneve] [I-D.ietf-nvo3-geneve]
IOAM: In-situ Operations, Administration, and Maintenance IOAM: In-situ Operations, Administration, and Maintenance
MTU: Maximum Transmit Unit MTU: Maximum Transmit Unit
NSH: Network Service Header [RFC8300] NSH: Network Service Header [RFC8300]
OAM: Operations, Administration, and Maintenance OAM: Operations, Administration, and Maintenance
PMTU Path MTU
POT: Proof of Transit POT: Proof of Transit
SFC: Service Function Chain SFC: Service Function Chain
SID: Segment Identifier SID: Segment Identifier
SR: Segment Routing SR: Segment Routing
VXLAN-GPE: Virtual eXtensible Local Area Network, Generic Protocol VXLAN-GPE: Virtual eXtensible Local Area Network, Generic Protocol
Extension [I-D.ietf-nvo3-vxlan-gpe] Extension [I-D.ietf-nvo3-vxlan-gpe]
3. Scope, Applicability, and Assumptions 4. Scope, Applicability, and Assumptions
IOAM deployment assumes a set of constraints, requirements, and IOAM deployment assumes a set of constraints, requirements, and
guiding principles which are described in this section. guiding principles which are described in this section.
Scope: This document defines the data fields and associated data Scope: This document defines the data fields and associated data
types for in-situ OAM. The in-situ OAM data field can be types for in-situ OAM. The in-situ OAM data field can be
encapsulated in a variety of protocols, including NSH, Segment encapsulated in a variety of protocols, including NSH, Segment
Routing, Geneve, IPv6, or IPv4. Specification details for these Routing, Geneve, IPv6, or IPv4. Specification details for these
different protocols are outside the scope of this document. different protocols are outside the scope of this document.
Deployment domain (or scope) of in-situ OAM deployment: IOAM is a Deployment domain (or scope) of in-situ OAM deployment: IOAM is a
network domain focused feature, with "network domain" being a set of network domain focused feature, with "network domain" being a set of
network devices or entities within a single administration. For network devices or entities within a single administration. For
example, a network domain can include an enterprise campus using example, a network domain can include an enterprise campus using
physical connections between devices or an overlay network using physical connections between devices or an overlay network using
virtual connections / tunnels for connectivity between said devices. virtual connections / tunnels for connectivity between said devices.
A network domain is defined by its perimeter or edge. Designers of A network domain is defined by its perimeter or edge. Designers of
protocol encapsulations for IOAM must specify mechanisms to ensure protocol encapsulations for IOAM specify mechanisms to ensure that
that IOAM data stays within an IOAM domain. In addition, the IOAM data stays within an IOAM domain. In addition, the operator of
operator of such a domain is expected to put provisions in place to such a domain is expected to put provisions in place to ensure that
ensure that IOAM data does not leak beyond the edge of an IOAM domain IOAM data does not leak beyond the edge of an IOAM domain using,for
using for example packet filtering methods. The operator should example, packet filtering methods. The operator has to consider the
consider the potential operational impact of IOAM to mechanisms such potential operational impact of IOAM to mechanisms such as ECMP
as ECMP processing (e.g. load-balancing schemes based on packet processing (e.g. load-balancing schemes based on packet length could
length could be impacted by the increased packet size due to IOAM), be impacted by the increased packet size due to IOAM), path MTU (i.e.
path MTU (i.e. ensure that the MTU of all links within a domain is ensure that the MTU of all links within a domain is sufficiently
sufficiently large to support the increased packet size due to IOAM) large to support the increased packet size due to IOAM) and ICMP
and ICMP message handling (i.e. in case of IPv6, IOAM support for message handling (i.e. in case of IPv6, IOAM support for ICMPv6 Echo
ICMPv6 Echo Request/Reply is desired which would translate into Request/Reply is desired which would translate into ICMPv6 extensions
ICMPv6 extensions to enable IOAM-Data-Fields to be copied from an to enable IOAM-Data-Fields to be copied from an Echo Request message
Echo Request message to an Echo Reply message). to an Echo Reply message).
IOAM control points: IOAM-Data-Fields are added to or removed from IOAM control points: IOAM-Data-Fields are added to or removed from
the live user traffic by the devices which form the edge of a domain. the live user traffic by the devices which form the edge of a domain.
Devices which form an IOAM-Domain can add, update or remove IOAM- Devices which form an IOAM-Domain can add, update or remove IOAM-
Data-Fields. Edge devices of an IOAM-Domain can be hosts or network Data-Fields. Edge devices of an IOAM-Domain can be hosts or network
devices. devices.
Traffic-sets that IOAM is applied to: IOAM can be deployed on all or Traffic-sets that IOAM is applied to: IOAM can be deployed on all or
only on subsets of the live user traffic. Using IOAM on a selected only on subsets of the live user traffic. Using IOAM on a selected
set of traffic (e.g., per interface, based on an access control list set of traffic (e.g., per interface, based on an access control list
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encapsulating protocols. The specification of how IOAM-Data-Fields encapsulating protocols. The specification of how IOAM-Data-Fields
are encapsulated into "parent" protocols, like e.g., NSH or IPv6 is are encapsulated into "parent" protocols, like e.g., NSH or IPv6 is
outside the scope of this document. outside the scope of this document.
Layering: If several encapsulation protocols (e.g., in case of Layering: If several encapsulation protocols (e.g., in case of
tunneling) are stacked on top of each other, IOAM-Data-Fields could tunneling) are stacked on top of each other, IOAM-Data-Fields could
be present at multiple layers. The behavior follows the ships-in- be present at multiple layers. The behavior follows the ships-in-
the-night model, i.e. IOAM-Data-Fields in one layer are independent the-night model, i.e. IOAM-Data-Fields in one layer are independent
from IOAM-Data-Fields in another layer. Layering allows operators to from IOAM-Data-Fields in another layer. Layering allows operators to
instrument the protocol layer they want to measure. The different instrument the protocol layer they want to measure. The different
layers could, but do not have to share the same IOAM encapsulation layers could, but do not have to, share the same IOAM encapsulation
mechanisms. mechanisms.
IOAM implementation: The definition of the IOAM-Data-Fields take the IOAM implementation: The definition of the IOAM-Data-Fields take the
specifics of devices with hardware data-plane and software data-plane specifics of devices with hardware data planes and software data
into account. planes into account.
4. IOAM Data-Fields, Types, Nodes 5. IOAM Data-Fields, Types, Nodes
This section details IOAM-related nomenclature and describes data This section details IOAM-related nomenclature and describes data
types such as IOAM-Data-Fields, IOAM-Types, IOAM-Namespaces as well types such as IOAM-Data-Fields, IOAM-Types, IOAM-Namespaces as well
as the different types of IOAM nodes. as the different types of IOAM nodes.
4.1. IOAM Data-Fields and Option-Types 5.1. IOAM Data-Fields and Option-Types
An IOAM-Data-Field is a set of bits with a defined format and An IOAM-Data-Field is a set of bits with a defined format and
meaning, which can be stored at a certain place in a packet for the meaning, which can be stored at a certain place in a packet for the
purpose of IOAM. purpose of IOAM.
To accommodate the different uses of IOAM, IOAM-Data-Fields fall into To accommodate the different uses of IOAM, IOAM-Data-Fields fall into
different categories. In IOAM these categories are referred to as different categories. In IOAM these categories are referred to as
IOAM-Option-Types. A common registry is maintained for IOAM-Option- IOAM-Option-Types. A common registry is maintained for IOAM-Option-
Types, see Section 7.2 for details. Corresponding to these IOAM- Types, see Section 8.1 for details. Corresponding to these IOAM-
Option-Types, different IOAM-Data-Fields are defined. IOAM-Data- Option-Types, different IOAM-Data-Fields are defined. IOAM-Data-
Fields can be encapsulated into a variety of protocols, such as NSH, Fields can be encapsulated into a variety of protocols, such as NSH,
Geneve, IPv6, etc. The definition of how IOAM-Data-Fields are Geneve, IPv6, etc. The definition of how IOAM-Data-Fields are
encapsulated into other protocols is outside the scope of this encapsulated into other protocols is outside the scope of this
document. document.
This document defines four IOAM-Option-Types: This document defines four IOAM-Option-Types:
o Pre-allocated Trace Option-Type o Pre-allocated Trace Option-Type
o Incremental Trace Option-Type o Incremental Trace Option-Type
o Proof of Transit (POT) Option-Type o Proof of Transit (POT) Option-Type
o Edge-to-Edge (E2E) Option-Type o Edge-to-Edge (E2E) Option-Type
4.2. IOAM-Domains and types of IOAM Nodes 5.2. IOAM-Domains and types of IOAM Nodes
IOAM is expected to be deployed in a specific domain. The part of IOAM is expected to be deployed in a specific domain. The part of
the network which employs IOAM is referred to as the "IOAM-Domain". the network which employs IOAM is referred to as the "IOAM-Domain".
One or more IOAM-Option-Types are added to a packet upon entering the One or more IOAM-Option-Types are added to a packet upon entering the
IOAM-Domain and are removed from the packet when exiting the domain. IOAM-Domain and are removed from the packet when exiting the domain.
Within the IOAM-Domain, the IOAM-Data-Fields MAY be updated by Within the IOAM-Domain, the IOAM-Data-Fields MAY be updated by
network nodes that the packet traverses. An IOAM-Domain consists of network nodes that the packet traverses. An IOAM-Domain consists of
"IOAM encapsulating nodes", "IOAM decapsulating nodes" and "IOAM "IOAM encapsulating nodes", "IOAM decapsulating nodes" and "IOAM
transit nodes". The role of a node (i.e. encapsulating, transit, transit nodes". The role of a node (i.e. encapsulating, transit,
decapsulating) is defined within an IOAM-Namespace (see below). A decapsulating) is defined within an IOAM-Namespace (see below). A
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Within the IOAM-Domain, the IOAM-Data-Fields MAY be updated by Within the IOAM-Domain, the IOAM-Data-Fields MAY be updated by
network nodes that the packet traverses. An IOAM-Domain consists of network nodes that the packet traverses. An IOAM-Domain consists of
"IOAM encapsulating nodes", "IOAM decapsulating nodes" and "IOAM "IOAM encapsulating nodes", "IOAM decapsulating nodes" and "IOAM
transit nodes". The role of a node (i.e. encapsulating, transit, transit nodes". The role of a node (i.e. encapsulating, transit,
decapsulating) is defined within an IOAM-Namespace (see below). A decapsulating) is defined within an IOAM-Namespace (see below). A
node can have different roles in different IOAM-Namespaces. node can have different roles in different IOAM-Namespaces.
A device which adds at least one IOAM-Option-Type to the packet is A device which adds at least one IOAM-Option-Type to the packet is
called the "IOAM encapsulating node", whereas a device which removes called the "IOAM encapsulating node", whereas a device which removes
an IOAM-Option-Type is referred to as the "IOAM decapsulating node". an IOAM-Option-Type is referred to as the "IOAM decapsulating node".
Nodes within the domain which are aware of IOAM data and read and/or Nodes within the domain which are aware of IOAM data and read and/or
write or process the IOAM data are called "IOAM transit nodes". IOAM write or process the IOAM data are called "IOAM transit nodes". IOAM
nodes which add or remove the IOAM-Data-Fields can also update the nodes which add or remove the IOAM-Data-Fields can also update the
IOAM-Data-Fields at the same time. Or in other words, IOAM IOAM-Data-Fields at the same time. Or in other words, IOAM
encapsulating or decapsulating nodes can also serve as IOAM transit encapsulating or decapsulating nodes can also serve as IOAM transit
nodes at the same time. Note that not every node in an IOAM domain nodes at the same time. Note that not every node in an IOAM domain
needs to be an IOAM transit node. For example, a deployment might needs to be an IOAM transit node. For example, a deployment might
require that packets traverse a set of firewalls which support IOAM. require that packets traverse a set of firewalls which support IOAM.
In that case, only the set of firewall nodes would be IOAM transit In that case, only the set of firewall nodes would be IOAM transit
nodes rather than all nodes. nodes rather than all nodes.
An "IOAM encapsulating node" incorporates one or more IOAM-Option- An "IOAM encapsulating node" incorporates one or more IOAM-Option-
Types (from the list of IOAM-Types, see Section 7.2) into packets Types (from the list of IOAM-Types, see Section 8.1) into packets
that IOAM is enabled for. If IOAM is enabled for a selected subset that IOAM is enabled for. If IOAM is enabled for a selected subset
of the traffic, the IOAM encapsulating node is responsible for of the traffic, the IOAM encapsulating node is responsible for
applying the IOAM functionality to the selected subset. applying the IOAM functionality to the selected subset.
An "IOAM transit node" updates one or more of the IOAM-Data-Fields. An "IOAM transit node" updates one or more of the IOAM-Data-Fields.
If both the Pre-allocated and the Incremental Trace Option-Types are If both the Pre-allocated and the Incremental Trace Option-Types are
present in the packet, each IOAM transit node will update at most one present in the packet, each IOAM transit node based on configuration
of these Option-Types. A transit node MUST NOT add new IOAM-Option- and available implementation of IOAM populates IOAM trace data in
Types to a packet, and MUST NOT change the IOAM-Data-Fields of an either Pre-allocated or Incremental Trace Option-Type but not both.
IOAM Edge-to-Edge Option-Type. A transit node MUST ignore IOAM-Option-Types that it does not
understand. A transit node MUST NOT add new IOAM-Option-Types to a
packet, MUST NOT remove IOAM-Option-Types from a packet, and MUST NOT
change the IOAM-Data-Fields of an IOAM Edge-to-Edge Option-Type.
An "IOAM decapsulating node" removes IOAM-Option-Type(s) from An "IOAM decapsulating node" removes IOAM-Option-Type(s) from
packets. packets.
The role of an IOAM-encapsulating, IOAM-transit or IOAM-decapsulating The role of an IOAM-encapsulating, IOAM-transit or IOAM-decapsulating
node is always performed within a specific IOAM-Namespace. This node is always performed within a specific IOAM-Namespace. This
means that an IOAM node which is e.g. an IOAM-decapsulating node for means that an IOAM node which is e.g. an IOAM-decapsulating node for
IOAM-Namespace "A" but not for IOAM-Namespace "B" will only remove IOAM-Namespace "A" but not for IOAM-Namespace "B" will only remove
the IOAM-Option-Types for IOAM-Namespace "A" from the packet. An the IOAM-Option-Types for IOAM-Namespace "A" from the packet. Note
IOAM decapsulating node situated at the edge of an IOAM domain MUST that this applies even for IOAM-Option-Types that the node does not
remove all IOAM-Option-Types and associated encapsulation headers for understand, for example an IOAM-Option-Type other than the four
all IOAM-Namespaces from the packet. described above, that is added in a future revision. An IOAM
decapsulating node situated at the edge of an IOAM domain MUST remove
all IOAM-Option-Types and associated encapsulation headers for all
IOAM-Namespaces from the packet.
IOAM-Namespaces allow for a namespace-specific definition and IOAM-Namespaces allow for a namespace-specific definition and
interpretation of IOAM-Data-Fields. An interface-id could for interpretation of IOAM-Data-Fields. An interface-id could for
example point to a physical interface (e.g., to understand which example point to a physical interface (e.g., to understand which
physical interface of an aggregated link is used when receiving or physical interface of an aggregated link is used when receiving or
transmitting a packet) whereas in another case it could refer to a transmitting a packet) whereas in another case it could refer to a
logical interface (e.g., in case of tunnels). Please refer to logical interface (e.g., in case of tunnels). Please refer to
Section 4.3 for details on IOAM-Namespaces. Section 5.3 for details on IOAM-Namespaces.
4.3. IOAM-Namespaces 5.3. IOAM-Namespaces
A subset or all of the IOAM-Option-Types and their corresponding A subset or all of the IOAM-Option-Types and their corresponding
IOAM-Data-Fields can be associated to an IOAM-Namespace. IOAM- IOAM-Data-Fields can be associated to an IOAM-Namespace. IOAM-
Namespaces add further context to IOAM-Option-Types and associated Namespaces add further context to IOAM-Option-Types and associated
IOAM-Data-Fields. Any IOAM-Namespace MUST interpret the IOAM-Option- IOAM-Data-Fields. Any IOAM-Namespace MUST interpret the IOAM-Option-
Types and associated IOAM-Data-Fields per the definition in this Types and associated IOAM-Data-Fields per the definition in this
document. IOAM-Namespaces group nodes to support different document. IOAM-Namespaces group nodes to support different
deployment approaches of IOAM (see a few example use-cases below) as deployment approaches of IOAM (see a few example use-cases below) as
well as resolve issues which can occur due to IOAM-Data-Fields not well as resolve issues which can occur due to IOAM-Data-Fields not
being globally unique (e.g. IOAM node identifiers do not have to be being globally unique (e.g. IOAM node identifiers do not have to be
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particular IOAM-Namespace. particular IOAM-Namespace.
An IOAM-Namespace is identified by a 16-bit namespace identifier An IOAM-Namespace is identified by a 16-bit namespace identifier
(Namespace-ID). IOAM-Namespace identifiers MUST be present and (Namespace-ID). IOAM-Namespace identifiers MUST be present and
populated in all IOAM-Option-Types. The Namespace-ID value is populated in all IOAM-Option-Types. The Namespace-ID value is
divided into two sub-ranges: divided into two sub-ranges:
o An operator-assigned range from 0x0001 to 0x7FFF o An operator-assigned range from 0x0001 to 0x7FFF
o An IANA-assigned range from 0x8000 to 0xFFFF o An IANA-assigned range from 0x8000 to 0xFFFF
The IANA-assigned range is intended to allow future extensions to The IANA-assigned range is intended to allow future extensions to
have new and interoperable IOAM functionality, while the operator- have new and interoperable IOAM functionality, while the operator-
assigned range is intended to be domain specific, and managed by the assigned range is intended to be domain specific, and managed by the
network operator. The Namespace-ID value of 0x0000 is default and network operator. The Namespace-ID value of 0x0000 is default and
known to all the nodes implementing IOAM. known to all the nodes implementing IOAM.
Namespace identifiers allow devices which are IOAM capable to Namespace identifiers allow devices which are IOAM capable to
determine: determine:
o whether IOAM-Option-Type(s) need to be processed by a device: If o whether IOAM-Option-Type(s) need to be processed by a device: If
the Namespace-ID contained in a packet does not match any the Namespace-ID contained in a packet does not match any
Namespace-ID the node is configured to operate on, then the node Namespace-ID the node is configured to operate on, then the node
MUST NOT change the contents of the IOAM-Data-Fields. MUST NOT change the contents of the IOAM-Data-Fields.
o which IOAM-Option-Type needs to be processed/updated in case there o which IOAM-Option-Type needs to be processed/updated in case there
are multiple IOAM-Option-Types present in the packet. Multiple are multiple IOAM-Option-Types present in the packet. Multiple
IOAM-Option-Types can be present in a packet in case of IOAM-Option-Types can be present in a packet in case of
overlapping IOAM-Domains or in case of a layered IOAM deployment. overlapping IOAM-Domains or in case of a layered IOAM deployment.
o whether IOAM-Option-Type(s) should be removed from the packet, o whether IOAM-Option-Type(s) has to be removed from the packet,
e.g. at a domain edge or domain boundary. e.g. at a domain edge or domain boundary.
IOAM-Namespaces support several different uses: IOAM-Namespaces support several different uses:
o IOAM-Namespaces can be used by an operator to distinguish o IOAM-Namespaces can be used by an operator to distinguish
different operational domains. Devices at domain edges can filter different operational domains. Devices at domain edges can filter
on Namespace-IDs to provide for proper IOAM-Domain isolation. on Namespace-IDs to provide for proper IOAM-Domain isolation.
o IOAM-Namespaces provide additional context for IOAM-Data-Fields o IOAM-Namespaces provide additional context for IOAM-Data-Fields
and thus ensure that IOAM-Data-Fields are unique and can be and thus ensure that IOAM-Data-Fields are unique and can be
interpreted properly by management stations or network interpreted properly by management stations or network
controllers. While, for example, the node identifier field controllers. While, for example, the node identifier field
(node_id, see below) does not need to be unique in a deployment (node_id, see below) does not need to be unique in a deployment
(e.g. an operator may wish to use different node identifiers for (e.g. if an operator wishes to use different node identifiers for
different IOAM layers, even within the same device; or node different IOAM layers, even within the same device; or node
identifiers might not be unique for other organizational reasons, identifiers might not be unique for other organizational reasons,
such as after a merger of two formerly separated organizations), such as after a merger of two formerly separated organizations),
the combination of node_id and Namespace-ID will always be unique. the combination of node_id and Namespace-ID will always be unique.
Similarly, IOAM-Namespaces can be used to define how certain IOAM- Similarly, IOAM-Namespaces can be used to define how certain IOAM-
Data-Fields are interpreted: IOAM offers three different timestamp Data-Fields are interpreted: IOAM offers three different timestamp
format options. The Namespace-ID can be used to determine the format options. The Namespace-ID can be used to determine the
timestamp format. IOAM-Data-Fields (e.g. buffer occupancy) which timestamp format. IOAM-Data-Fields (e.g. buffer occupancy) which
do not have a unit associated are to be interpreted within the do not have a unit associated are to be interpreted within the
context of a IOAM-Namespace. context of a IOAM-Namespace.
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hardware or operational limitations on the size of the trace data hardware or operational limitations on the size of the trace data
that can be added and processed, preventing collection of a full that can be added and processed, preventing collection of a full
trace for a flow. trace for a flow.
* Assigning different IOAM Namespace-IDs to different sets of * Assigning different IOAM Namespace-IDs to different sets of
nodes or network partitions and using the Namespace-ID as a nodes or network partitions and using the Namespace-ID as a
selector at the IOAM encapsulating node, a full trace for a selector at the IOAM encapsulating node, a full trace for a
flow could be collected and constructed via partial traces in flow could be collected and constructed via partial traces in
different packets of the same flow. Example: An operator could different packets of the same flow. Example: An operator could
choose to group the devices of a domain into two IOAM- choose to group the devices of a domain into two IOAM-
Namespaces, in a way that at average, only every second hop Namespaces, in a way that on average, only every second hop
would be recorded by any device. To retrieve a full view of would be recorded by any device. To retrieve a full view of
the deployment, the captured IOAM-Data-Fields of the two IOAM- the deployment, the captured IOAM-Data-Fields of the two IOAM-
Namespaces need to be correlated. Namespaces need to be correlated.
* Assigning different IOAM Namespace-IDs to different sets of * Assigning different IOAM Namespace-IDs to different sets of
nodes or network partitions and using a separate instance of an nodes or network partitions and using a separate instance of an
IOAM-Option-Type for each Namespace-ID, a full trace for a flow IOAM-Option-Type for each Namespace-ID, a full trace for a flow
could be collected and constructed via partial traces from each could be collected and constructed via partial traces from each
IOAM-Option-Type in each of the packets in the flow. Example: IOAM-Option-Type in each of the packets in the flow. Example:
An operator could choose to group the devices of a domain into An operator could choose to group the devices of a domain into
two IOAM-Namespaces, in a way that each IOAM-Namespace is two IOAM-Namespaces, in a way that each IOAM-Namespace is
represented by one of two IOAM-Option-Types in the packet. represented by one of two IOAM-Option-Types in the packet.
Each node would record data only for the IOAM-Namespace that it Each node would record data only for the IOAM-Namespace that it
belongs to, ignoring the other IOAM-Option-Type with a IOAM- belongs to, ignoring the other IOAM-Option-Type with a IOAM-
Namespace to which it doesn't belong. To retrieve a full view Namespace to which it doesn't belong. To retrieve a full view
of the deployment, the captured IOAM-Data-Fields of the two of the deployment, the captured IOAM-Data-Fields of the two
IOAM-Namespaces need to be correlated. IOAM-Namespaces need to be correlated.
4.4. IOAM Trace Option-Types 5.4. IOAM Trace Option-Types
"IOAM tracing data" is expected to be either collected at every IOAM "IOAM tracing data" is expected to be either collected at every IOAM
transit node that a packet traverses to ensure visibility into the transit node that a packet traverses to ensure visibility into the
entire path a packet takes within an IOAM-Domain. I.e., in a typical entire path a packet takes within an IOAM-Domain. I.e., in a typical
deployment all nodes in an IOAM-Domain would participate in IOAM and deployment all nodes in an IOAM-Domain would participate in IOAM and
thus be IOAM transit nodes, IOAM encapsulating or IOAM decapsulating thus be IOAM transit nodes, IOAM encapsulating or IOAM decapsulating
nodes. If not all nodes within a domain support IOAM functionality nodes. If not all nodes within a domain support IOAM functionality
as defined in this document, IOAM tracing information (i.e., node as defined in this document, IOAM tracing information (i.e., node
data, see below) will only be collected on those nodes which support data, see below) will only be collected on those nodes which support
IOAM functionality as defined in this document. Nodes which do not IOAM functionality as defined in this document. Nodes which do not
support IOAM functionality as defined in this document will forward support IOAM functionality as defined in this document will forward
the packet without any changes to the IOAM-Data-Fields. The maximum the packet without any changes to the IOAM-Data-Fields. The maximum
number of hops and the minimum path MTU of the IOAM domain is assumed number of hops and the minimum path MTU of the IOAM domain is assumed
to be known. to be known. An overflow indicator (O-bit) is defined as one of the
ways to deal with situations where the PMTU was underestimated, i.e.
where the number of hops which are IOAM capable exceeds the available
space in the packet.
To optimize hardware and software implementations IOAM tracing is To optimize hardware and software implementations, IOAM tracing is
defined as two separate options. Any deployment MAY choose to defined as two separate options. Any deployment MAY choose to
configure and support one or both of the following options. configure and support one or both of the following options.
Pre-allocated Trace-Option: This trace option is defined as a Pre-allocated Trace-Option: This trace option is defined as a
container of node data fields (see below) with pre-allocated space container of node data fields (see below) with pre-allocated space
for each node to populate its information. This option is useful for each node to populate its information. This option is useful
for implementations where it is efficient to allocate the space for implementations where it is efficient to allocate the space
once and index into the array to populate the data during transit once and index into the array to populate the data during transit
(e.g., software forwarders often fall into this class). The IOAM (e.g., software forwarders often fall into this class). The IOAM
encapsulating node allocates space for Pre-allocated Trace Option- encapsulating node allocates space for Pre-allocated Trace Option-
Type in the packet and sets corresponding fields in this IOAM- Type in the packet and sets corresponding fields in this IOAM-
Option-Type. The IOAM encapsulating node allocates an array which Option-Type. The IOAM encapsulating node allocates an array which
is used to store operational data retrieved from every node while is used to store operational data retrieved from every node while
the packet traverses the domain. IOAM transit nodes update the the packet traverses the domain. IOAM transit nodes update the
content of the array, and possibly update the checksums of outer content of the array, and possibly update the checksums of outer
headers. A pointer which is part of the IOAM trace data, points headers. A pointer which is part of the IOAM trace data, points
to the next empty slot in the array. An IOAM transit node that to the next empty slot in the array. An IOAM transit node that
updates the content of the pre-allocated option also updates the updates the content of the pre-allocated option also updates the
value of the pointer, which specifies where the next IOAM transit value of the pointer, which specifies where the next IOAM transit
node fills in its data.The "node data list" array (see below) in node fills in its data. The "node data list" array (see below) in
the packet is populated iteratively as the packet traverses the the packet is populated iteratively as the packet traverses the
network, starting with the last entry of the array, i.e., "node network, starting with the last entry of the array, i.e., "node
data list [n]" is the first entry to be populated, "node data list data list [n]" is the first entry to be populated, "node data list
[n-1]" is the second one, etc. [n-1]" is the second one, etc.
Incremental Trace-Option: This trace option is defined as a Incremental Trace-Option: This trace option is defined as a
container of node data fields where each node allocates and pushes container of node data fields where each node allocates and pushes
its node data immediately following the option header. This type its node data immediately following the option header. This type
of trace recording is useful for some of the hardware of trace recording is useful for some of the hardware
implementations as it eliminates the need for the transit network implementations as it eliminates the need for the transit network
elements to read the full array in the option and allows for elements to read the full array in the option and allows for
arbitrarily long packets as the MTU allows. The IOAM arbitrarily long packets as the MTU allows. The IOAM
encapsulating node allocates space for the Incremental Trace encapsulating node allocates space for the Incremental Trace
Option-Type. Based on operational state and configuration, the Option-Type. Based on operational state and configuration, the
IOAM encapsulating node sets the fields in the Option-Type that IOAM encapsulating node sets the fields in the Option-Type that
control what IOAM-Data-Fields should be collected and how large control what IOAM-Data-Fields have to be collected and how large
the node data list can grow. IOAM transit nodes push their node the node data list can grow. IOAM transit nodes push their node
data to the node data list, decrease the remaining length data to the node data list, decrease the remaining length
available to subsequent nodes and adjust the lengths and possibly available to subsequent nodes and adjust the lengths and possibly
checksums in outer headers. checksums in outer headers.
A particular implementation of IOAM MAY choose to support only one of A particular implementation of IOAM MAY choose to support only one of
the two trace option types. In the event that both options are the two trace option types. In the event that both options are
utilized at the same time, the Incremental Trace-Option MUST be utilized at the same time, the Incremental Trace-Option MUST be
placed before the Pre-allocated Trace-Option. Deployments which mix placed before the Pre-allocated Trace-Option. Deployments which mix
devices which either the Incremental Trace-Option or the Pre- devices with either the Incremental Trace-Option or the Pre-allocated
allocated Trace-Option could result in both Option-Types being Trace-Option could result in both Option-Types being present in a
present in a packet. Given that the operator knows which equipment packet. Given that the operator knows which equipment is deployed in
is deployed in a particular IOAM, the operator will decide by means a particular IOAM, the operator will decide by means of configuration
of configuration which type(s) of trace options will be used for a which type(s) of trace options will be used for a particular domain.
particular domain.
Every node data entry holds information for a particular IOAM transit Every node data entry holds information for a particular IOAM transit
node that is traversed by a packet. The IOAM decapsulating node node that is traversed by a packet. The IOAM decapsulating node
removes the IOAM-Option-Type(s) and processes and/or exports the removes the IOAM-Option-Type(s) and processes and/or exports the
associated data. Like all IOAM-Data-Fields, the IOAM-Data-Fields of associated data. Like all IOAM-Data-Fields, the IOAM-Data-Fields of
the IOAM-Trace-Option-Types are defined in the context of an IOAM- the IOAM-Trace-Option-Types are defined in the context of an IOAM-
Namespace. Namespace.
IOAM tracing can collect the following types of information: IOAM tracing can collect the following types of information:
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o Identification of the interface that a packet was sent out on, o Identification of the interface that a packet was sent out on,
i.e. egress interface. i.e. egress interface.
o Time of day when the packet was processed by the node as well as o Time of day when the packet was processed by the node as well as
the transit delay. Different definitions of processing time are the transit delay. Different definitions of processing time are
feasible and expected, though it is important that all devices of feasible and expected, though it is important that all devices of
an in-situ OAM domain follow the same definition. an in-situ OAM domain follow the same definition.
o Generic data: Format-free information where syntax and semantic of o Generic data: Format-free information where syntax and semantic of
the information is defined by the operator in a specific the information is defined by the operator in a specific
deployment. For a specific IOAM-Namespace, all IOAM nodes should deployment. For a specific IOAM-Namespace, all IOAM nodes have to
interpret the generic data the same way. Examples for generic interpret the generic data the same way. Examples for generic
IOAM data include geo-location information (location of the node IOAM data include geo-location information (location of the node
at the time the packet was processed), buffer queue fill level or at the time the packet was processed), buffer queue fill level or
cache fill level at the time the packet was processed, or even a cache fill level at the time the packet was processed, or even a
battery charge level. battery charge level.
o Information to detect whether IOAM trace data was added at every o Information to detect whether IOAM trace data was added at every
hop or whether certain hops in the domain weren't IOAM transit hop or whether certain hops in the domain weren't IOAM transit
nodes. nodes.
4.4.1. Pre-allocated and Incremental Trace Option-Types 5.4.1. Pre-allocated and Incremental Trace Option-Types
The IOAM Pre-allocated Trace-Option and the IOAM Incremental Trace- The IOAM Pre-allocated Trace-Option and the IOAM Incremental Trace-
Option have similar formats. Except where noted below, the internal Option have similar formats. Except where noted below, the internal
formats and fields of the two trace options are identical. Both formats and fields of the two trace options are identical. Both
Trace-Options consist of a fixed size "trace option header" and a Trace-Options consist of a fixed size "trace option header" and a
variable data space to store gathered data, the "node data list". An variable data space to store gathered data, the "node data list". An
IOAM transit node (that is not an IOAM encapsulating node or IOAM IOAM transit node (that is not an IOAM encapsulating node or IOAM
decapsulating node) MUST NOT modify any of the fields in the fixed decapsulating node) MUST NOT modify any of the fields in the fixed
size "trace option header", other than "flags" and "RemainingLen", size "trace option header", other than "flags" and "RemainingLen",
i.e. an IOAM transit node MUST NOT modify the Namespace-ID, NodeLen, i.e. an IOAM transit node MUST NOT modify the Namespace-ID, NodeLen,
skipping to change at page 13, line 36 skipping to change at page 14, line 4
~ ... ~ S ~ ... ~ S
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ p +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ p
| | a | | a
| node data list [n-1] | c | node data list [n-1] | c
| | e | | e
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | | | | |
| node data list [n] | | | node data list [n] | |
| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
Namespace-ID: 16-bit identifier of an IOAM-Namespace. The Namespace-ID: 16-bit identifier of an IOAM-Namespace. The
Namespace-ID value of 0x0000 is defined as the default value and Namespace-ID value of 0x0000 is defined as the default value and
MUST be known to all the nodes implementing IOAM. For any other MUST be known to all the nodes implementing IOAM. For any other
Namespace-ID value that does not match any Namespace-ID the node Namespace-ID value that does not match any Namespace-ID the node
is configured to operate on, the node MUST NOT change the contents is configured to operate on, the node MUST NOT change the contents
of the IOAM-Data-Fields. of the IOAM-Data-Fields.
NodeLen: 5-bit unsigned integer. This field specifies the length of NodeLen: 5-bit unsigned integer. This field specifies the length of
data added by each node in multiples of 4-octets, excluding the data added by each node in multiples of 4-octets, excluding the
length of the "Opaque State Snapshot" field. length of the "Opaque State Snapshot" field.
If IOAM-Trace-Type bit 22 is not set, then NodeLen specifies the If IOAM-Trace-Type bit 22 is not set, then NodeLen specifies the
actual length added by each node. If IOAM-Trace-Type bit 22 is actual length added by each node. If IOAM-Trace-Type bit 22 is
set, then the actual length added by a node would be (NodeLen + set, then the actual length added by a node would be (NodeLen +
length of the "Opaque State Snapshot" field) in 4 octet units. length of the "Opaque State Snapshot" field) in 4 octet units.
For example, if 3 IOAM-Trace-Type bits are set and none of them For example, if 3 IOAM-Trace-Type bits are set and none of them
are wide, then NodeLen would be 3. If 3 IOAM-Trace-Type bits are are wide, then NodeLen would be 3. If 3 IOAM-Trace-Type bits are
set and 2 of them are wide, then NodeLen would be 5. set and 2 of them are wide, then NodeLen would be 5.
An IOAM encapsulating node must set NodeLen. An IOAM encapsulating node MUST set NodeLen.
A node receiving an IOAM Pre-allocated or Incremental Trace-Option A node receiving an IOAM Pre-allocated or Incremental Trace-Option
may rely on the NodeLen value, or it may ignore the NodeLen value relies on the NodeLen value, or it can ignore the NodeLen value
and calculate the node length from the IOAM-Trace-Type bits (see and calculate the node length from the IOAM-Trace-Type bits (see
below). below).
Flags 4-bit field. Flags are allocated by IANA, as specified in Flags 4-bit field. Flags are allocated by IANA, as specified in
Section 7.4. This document allocates a single flag as follows: Section 8.3. This document allocates a single flag as follows:
Bit 0 "Overflow" (O-bit) (most significant bit). This bit is set Bit 0 "Overflow" (O-bit) (most significant bit). If there are
by the network element if there are not enough octets left to not enough octets left to record node data, the network element
record node data, no field is added and the overflow "O-bit" MUST NOT add any fields and MUST set the overflow "O-bit" to
must be set to "1" in the IOAM-Trace-Option header. This is "1" in the IOAM-Trace-Option header. This is useful for
useful for transit nodes to ignore further processing of the transit nodes to ignore further processing of the option.
option.
RemainingLen: 7-bit unsigned integer. This field specifies the data RemainingLen: 7-bit unsigned integer. This field specifies the data
space in multiples of 4-octets remaining for recording the node space in multiples of 4-octets remaining for recording the node
data, before the node data list is considered to have overflowed. data, before the node data list is considered to have overflowed.
Given that the sender knows the minimum path MTU, the sender MAY Given that the sender knows the path MTU (PMTU), the sender MAY
set the initial value of RemainingLen according to the number of set the initial value of RemainingLen according to the number of
node data bytes allowed before exceeding the MTU. Subsequent node data bytes allowed before exceeding the MTU. Subsequent
nodes can carry out a simple comparison between RemainingLen and nodes can carry out a simple comparison between RemainingLen and
NodeLen, along with the length of the "Opaque State Snapshot" if NodeLen, along with the length of the "Opaque State Snapshot" if
applicable, to determine whether or not data can be added by this applicable, to determine whether or not data can be added by this
node. When node data is added, the node MUST decrease node. When node data is added, the node MUST decrease
RemainingLen by the amount of data added. In the pre-allocated RemainingLen by the amount of data added. In the pre-allocated
trace option, RemainingLength is used to derive the offset in data trace option, RemainingLen is used to derive the offset in data
space to record the node data element. Specifically, the space to record the node data element. Specifically, the
recording of the node data element would start from RemainingLen - recording of the node data element would start from RemainingLen -
NodeLen - sizeof(opaque snapshot) in 4 octet units. NodeLen - sizeof(opaque snapshot) in 4 octet units. If
RemainingLen in a pre-allocated trace option exceeds the length of
the option, as specified in the preceding header, then the node
MUST NOT add any fields.
IOAM-Trace-Type: A 24-bit identifier which specifies which data IOAM-Trace-Type: A 24-bit identifier which specifies which data
types are used in this node data list. types are used in this node data list.
The IOAM-Trace-Type value is a bit field. The following bits are The IOAM-Trace-Type value is a bit field. The following bits are
defined in this document, with details on each bit described in defined in this document, with details on each bit described in
the Section 4.4.2. The order of packing the data fields in each the Section 5.4.2. The order of packing the data fields in each
node data element follows the bit order of the IOAM-Trace-Type node data element follows the bit order of the IOAM-Trace-Type
field, as follows: field, as follows:
Bit 0 (Most significant bit) When set indicates presence of Bit 0 (Most significant bit) When set, indicates presence of
Hop_Lim and node_id (short format) in the node data. Hop_Lim and node_id (short format) in the node data.
Bit 1 When set indicates presence of ingress_if_id and Bit 1 When set, indicates presence of ingress_if_id and
egress_if_id (short format) in the node data. egress_if_id (short format) in the node data.
Bit 2 When set indicates presence of timestamp seconds in the Bit 2 When set, indicates presence of timestamp seconds in the
node data. node data.
Bit 3 When set indicates presence of timestamp subseconds in Bit 3 When set, indicates presence of timestamp subseconds in
the node data. the node data.
Bit 4 When set indicates presence of transit delay in the node Bit 4 When set, indicates presence of transit delay in the node
data. data.
Bit 5 When set indicates presence of IOAM-Namespace specific Bit 5 When set, indicates presence of IOAM-Namespace specific
data (short format) in the node data. data (short format) in the node data.
Bit 6 When set indicates presence of queue depth in the node Bit 6 When set, indicates presence of queue depth in the node
data. data.
Bit 7 When set indicates presence of the Checksum Complement Bit 7 When set, indicates presence of the Checksum Complement
node data. node data.
Bit 8 When set indicates presence of Hop_Lim and node_id in Bit 8 When set, indicates presence of Hop_Lim and node_id in
wide format in the node data. wide format in the node data.
Bit 9 When set indicates presence of ingress_if_id and Bit 9 When set, indicates presence of ingress_if_id and
egress_if_id in wide format in the node data. egress_if_id in wide format in the node data.
Bit 10 When set indicates presence of IOAM-Namespace specific Bit 10 When set, indicates presence of IOAM-Namespace specific
data in wide format in the node data. data in wide format in the node data.
Bit 11 When set indicates presence of buffer occupancy in the Bit 11 When set, indicates presence of buffer occupancy in the
node data. node data.
Bit 12-21 Undefined. An IOAM encapsulating node MUST set the Bit 12-21 Undefined. An IOAM encapsulating node MUST set the
value of each of these bits to 0. If an IOAM transit value of each of these bits to 0. If an IOAM transit
node receives a packet with one or more of these bits set node receives a packet with one or more of these bits set
to 1, it must either: to 1, it MUST either:
1. Add corresponding node data filled with the reserved 1. Add corresponding node data filled with the reserved
value 0xFFFFFFFF, after the node data fields for the value 0xFFFFFFFF, after the node data fields for the
IOAM-Trace-Type bits defined above, such that the IOAM-Trace-Type bits defined above, such that the
total node data added by this node in units of total node data added by this node in units of
4-octets is equal to NodeLen, or 4-octets is equal to NodeLen, or
2. Not add any node data fields to the packet, even for 2. Not add any node data fields to the packet, even for
the IOAM-Trace-Type bits defined above. the IOAM-Trace-Type bits defined above.
Bit 22 When set indicates presence of variable length Opaque Bit 22 When set, indicates presence of variable length Opaque
State Snapshot field. State Snapshot field.
Bit 23 Reserved: Must be set to zero upon transmission and Bit 23 Reserved: MUST be set to zero upon transmission and
ignored upon receipt. ignored upon receipt.
Section 4.4.2 describes the IOAM-Data-Types and their formats. Section 5.4.2 describes the IOAM-Data-Types and their formats.
Within an IOAM-Domain possible combinations of these bits making Within an IOAM-Domain possible combinations of these bits making
the IOAM-Trace-Type can be restricted by configuration knobs. the IOAM-Trace-Type can be restricted by configuration knobs.
Reserved: 8-bits. An IOAM encapsulating node MUST set the value to Reserved: 8-bits. An IOAM encapsulating node MUST set the value to
zero upon transmission. IOAM transit nodes must ignore the zero upon transmission. IOAM transit nodes MUST ignore the
received value. received value.
Node data List [n]: Variable-length field. This is a list of node Node data List [n]: Variable-length field. This is a list of node
data elements where the content of each node data element is data elements where the content of each node data element is
determined by the IOAM-Trace-Type. The order of packing the data determined by the IOAM-Trace-Type. The order of packing the data
fields in each node data element follows the bit order of the fields in each node data element follows the bit order of the
IOAM-Trace-Type field. Each node MUST prepend its node data IOAM-Trace-Type field. Each node MUST prepend its node data
element in front of the node data elements that it received, such element in front of the node data elements that it received, such
that the transmitted node data list begins with this node's data that the transmitted node data list begins with this node's data
element as the first populated element in the list. The last node element as the first populated element in the list. The last node
data element in this list is the node data of the first IOAM data element in this list is the node data of the first IOAM
capable node in the path. Populating the node data list in this capable node in the path. Populating the node data list in this
way ensures that the order of node data list is the same for way ensures that the order of node data list is the same for
incremental and pre-allocated trace options. In the pre-allocated incremental and pre-allocated trace options. In the pre-allocated
trace option, the index contained in RemainingLen identifies the trace option, the index contained in RemainingLen identifies the
offset for current active node data to be populated. offset for current active node data to be populated.
4.4.2. IOAM node data fields and associated formats 5.4.2. IOAM node data fields and associated formats
All the IOAM-Data-Fields MUST be 4-octet aligned. If a node which is All the IOAM-Data-Fields MUST be 4-octet aligned. If a node which is
supposed to update an IOAM-Data-Field is not capable of populating supposed to update an IOAM-Data-Field is not capable of populating
the value of a field set in the IOAM-Trace-Type, the field value MUST the value of a field set in the IOAM-Trace-Type, the field value MUST
be set to 0xFFFFFFFF for 4-octet fields or 0xFFFFFFFFFFFFFFFF for be set to 0xFFFFFFFF for 4-octet fields or 0xFFFFFFFFFFFFFFFF for
8-octet fields, indicating that the value is not populated, except 8-octet fields, indicating that the value is not populated, except
when explicitly specified in the field description below. when explicitly specified in the field description below.
Some IOAM-Data-Fields defined below, such as interface identifiers or Some IOAM-Data-Fields defined below, such as interface identifiers or
IOAM-Namespace specific data, are defined in both "short format" as IOAM-Namespace specific data, are defined in both "short format" as
well as "wide format". Their use is not exclusive. A deployment well as "wide format". Their use is not exclusive. A deployment
could choose to leverage both. For example, ingress_if_id_(short could choose to leverage both. For example, ingress_if_id_(short
format) could be an identifier for the physical interface, whereas format) could be an identifier for the physical interface, whereas
ingress_if_id_(wide format) could be an identifier for a logical sub- ingress_if_id_(wide format) could be an identifier for a logical sub-
interface of that physical interface. interface of that physical interface.
Data field and associated data type for each of the IOAM-Data-Fields Data fields and associated data types for each of the IOAM-Data-
is shown below: Fields are specified in the following sections.
Hop_Lim and node_id short format: 4-octet field defined as follows: 5.4.2.1. Hop_Lim and node_id short format
The "Hop_Lim and node_id short format" field is a 4-octet field that
is defined as follows:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id | | Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit value
value in the packet at the node that records this data. Hop in the packet at the node that records this data. Hop Limit
Limit information is used to identify the location of the node information is used to identify the location of the node in the
in the communication path. This is copied from the lower communication path. This is copied from the lower layer, e.g.,
layer, e.g., TTL value in IPv4 header or hop limit field from TTL value in IPv4 header or hop limit field from IPv6 header of
IPv6 header of the packet when the packet is ready for the packet when the packet is ready for transmission. The
transmission. The semantics of the Hop_Lim field depend on the semantics of the Hop_Lim field depend on the lower layer protocol
lower layer protocol that IOAM is encapsulated into, and that IOAM is encapsulated into, and therefore its specific
therefore its specific semantics are outside the scope of this semantics are outside the scope of this memo. The value of this
memo. The value of this field MUST be set to 0xff when the field MUST be set to 0xff when the lower level does not have a
lower level does not have a TTL/Hop limit equivalent field. TTL/Hop limit equivalent field.
node_id: 3-octet unsigned integer. Node identifier field to node_id: 3-octet unsigned integer. Node identifier field to
uniquely identify a node within the IOAM-Namespace and uniquely identify a node within the IOAM-Namespace and associated
associated IOAM-Domain. The procedure to allocate, manage and IOAM-Domain. The procedure to allocate, manage and map the
map the node_ids is beyond the scope of this document. node_ids is beyond the scope of this document.
ingress_if_id and egress_if_id: 4-octet field defined as follows: 5.4.2.2. ingress_if_id and egress_if_id
The "ingress_if_id and egress_if_id" field is a 4-octet field that is
defined as follows:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id | egress_if_id | | ingress_if_id | egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ingress_if_id: 2-octet unsigned integer. Interface identifier to ingress_if_id: 2-octet unsigned integer. Interface identifier to
record the ingress interface the packet was received on. record the ingress interface the packet was received on.
egress_if_id: 2-octet unsigned integer. Interface identifier to egress_if_id: 2-octet unsigned integer. Interface identifier to
record the egress interface the packet is forwarded out of. record the egress interface the packet is forwarded out of.
Note that due to the fact that IOAM uses its own IOAM-Namespaces Note that due to the fact that IOAM uses its own IOAM-Namespaces for
for IOAM-Data-Fields, data fields like interface identifiers can IOAM-Data-Fields, data fields like interface identifiers can be used
be used in a flexible way to represent system resources that are in a flexible way to represent system resources that are associated
associated with ingressing or egressing packets, i.e. with ingressing or egressing packets, i.e. ingress_if_id could
ingress_if_id could represent a physical interface, a virtual or represent a physical interface, a virtual or logical interface, or
logical interface, or even a queue. even a queue.
timestamp seconds: 4-octet unsigned integer. Absolute timestamp in 5.4.2.3. timestamp seconds
seconds that specifies the time at which the packet was received
by the node. This field has three possible formats; based on
either PTP [IEEE1588v2], NTP [RFC5905], or POSIX [POSIX]. The
three timestamp formats are specified in Section 5. In all three
cases, the Timestamp Seconds field contains the 32 most
significant bits of the timestamp format that is specified in
Section 5. If a node is not capable of populating this field, it
assigns the value 0xFFFFFFFF. Note that this is a legitimate
value that is valid for 1 second in approximately 136 years; the
analyzer should correlate several packets or compare the timestamp
value to its own time-of-day in order to detect the error
indication.
timestamp subseconds: 4-octet unsigned integer. Absolute timestamp The "timestamp seconds" field is a 4-octet unsigned integer field.
in subseconds that specifies the time at which the packet was Absolute timestamp in seconds that specifies the time at which the
received by the node. This field has three possible formats; packet was received by the node. This field has three possible
based on either PTP [IEEE1588v2], NTP [RFC5905], or POSIX [POSIX]. formats; based on either PTP [IEEE1588v2], NTP [RFC5905], or POSIX
The three timestamp formats are specified in Section 5. In all [POSIX]. The three timestamp formats are specified in Section 6. In
three cases, the Timestamp Subseconds field contains the 32 least all three cases, the Timestamp Seconds field contains the 32 most
significant bits of the timestamp format that is specified in significant bits of the timestamp format that is specified in
Section 5. If a node is not capable of populating this field, it Section 6. If a node is not capable of populating this field, it
assigns the value 0xFFFFFFFF. Note that this is a legitimate assigns the value 0xFFFFFFFF. Note that this is a legitimate value
value in the NTP format, valid for approximately 233 picoseconds that is valid for 1 second in approximately 136 years; the analyzer
in every second. If the NTP format is used the analyzer should has to correlate several packets or compare the timestamp value to
correlate several packets in order to detect the error indication. its own time-of-day in order to detect the error indication.
transit delay: 4-octet unsigned integer in the range 0 to 2^31-1. 5.4.2.4. timestamp subseconds
It is the time in nanoseconds the packet spent in the transit
node. This can serve as an indication of the queuing delay at the The "timestamp subseconds" field is a 4-octet unsigned integer field.
node. If the transit delay exceeds 2^31-1 nanoseconds then the Absolute timestamp in subseconds that specifies the time at which the
top bit 'O' is set to indicate overflow and value set to packet was received by the node. This field has three possible
0x80000000. When this field is part of the data field but a node formats; based on either PTP [IEEE1588v2], NTP [RFC5905], or POSIX
populating the field is not able to fill it, the field position in [POSIX]. The three timestamp formats are specified in Section 6. In
the field must be filled with value 0xFFFFFFFF to mean not all three cases, the Timestamp Subseconds field contains the 32 least
populated. significant bits of the timestamp format that is specified in
Section 6. If a node is not capable of populating this field, it
assigns the value 0xFFFFFFFF. Note that this is a legitimate value
in the NTP format, valid for approximately 233 picoseconds in every
second. If the NTP format is used the analyzer has to correlate
several packets in order to detect the error indication.
5.4.2.5. transit delay
The "transit delay" field is a 4-octet unsigned integer in the range
0 to 2^31-1. It is the time in nanoseconds the packet spent in the
transit node. This can serve as an indication of the queuing delay
at the node. If the transit delay exceeds 2^31-1 nanoseconds then
the top bit 'O' is set to indicate overflow and value set to
0x80000000. When this field is part of the data field but a node
populating the field is not able to fill it, the field position in
the field MUST be filled with value 0xFFFFFFFF to mean not populated.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|O| transit delay | |O| transit delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
namespace specific data: 4-octet field which can be used by the node 5.4.2.6. namespace specific data
to add IOAM-Namespace specific data. This represents a "free-
format" 4-octet bit field with its semantics defined in the The "namespace specific data" field is a 4-octet field which can be
context of a specific IOAM-Namespace. used by the node to add IOAM-Namespace specific data. This
represents a "free-format" 4-octet bit field with its semantics
defined in the context of a specific IOAM-Namespace.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| namespace specific data | | namespace specific data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
queue depth: 4-octet unsigned integer field. This field indicates 5.4.2.7. queue depth
the current length of the egress interface queue of the interface
from where the packet is forwarded out. The queue depth is The "queue depth" field is a 4-octet unsigned integer field. This
expressed as the current number of memory buffers used by the field indicates the current length of the egress interface queue of
queue (a packet may consume one or more memory buffers, depending the interface from where the packet is forwarded out. The queue
on its size). depth is expressed as the current amount of memory buffers used by
the queue (a packet could consume one or more memory buffers,
depending on its size).
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| queue depth | | queue depth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Hop_Lim and node_id wide: 8-octet field defined as follows: 5.4.2.8. Checksum Complement
The "Checksum Complement" field is a 4-octet node data which contains
a 4-octet Checksum Complement field. The Checksum Complement is
useful when IOAM is transported over encapsulations that make use of
a UDP transport, such as VXLAN-GPE or Geneve. Without the Checksum
Complement, nodes adding IOAM node data update the UDP Checksum field
following the recommendation of the encapsulation protocols. When
the Checksum Complement is present, an IOAM encapsulating node or
IOAM transit node adding node data MUST carry out one of the
following two alternatives in order to maintain the correctness of
the UDP Checksum value:
1. Recompute the UDP Checksum field.
2. Use the Checksum Complement to make a checksum-neutral update in
the UDP payload; the Checksum Complement is assigned a value that
complements the rest of the node data fields that were added by
the current node, causing the existing UDP Checksum field to
remain correct.
IOAM decapsulating nodes MUST recompute the UDP Checksum field, since
they do not know whether previous hops modified the UDP Checksum
field or the Checksum Complement field.
Checksum Complement fields are used in a similar manner in [RFC7820]
and [RFC7821].
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum Complement |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
5.4.2.9. Hop_Lim and node_id wide
The "Hop_Lim and node_id wide" field is an 8-octet field defined as
follows:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id ~ | Hop_Lim | node_id ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ node_id (contd) | ~ node_id (contd) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit value
value in the packet at the node that records this data. Hop in the packet at the node that records this data. Hop Limit
Limit information is used to identify the location of the node information is used to identify the location of the node in the
in the communication path. This is copied from the lower layer communication path. This is copied from the lower layer for e.g.
for e.g. TTL value in IPv4 header or hop limit field from IPv6 TTL value in IPv4 header or hop limit field from IPv6 header of
header of the packet. The semantics of the Hop_Lim field the packet. The semantics of the Hop_Lim field depend on the
depend on the lower layer protocol that IOAM is encapsulated lower layer protocol that IOAM is encapsulated into, and therefore
into, and therefore its specific semantics are outside the its specific semantics are outside the scope of this memo. The
scope of this memo. The value of this field MUST be set to value of this field MUST be set to 0xff when the lower level does
0xff when the lower level does not have a TTL/Hop limit not have a TTL/Hop limit equivalent field.
equivalent field.
node_id: 7-octet unsigned integer. Node identifier field to node_id: 7-octet unsigned integer. Node identifier field to
uniquely identify a node within the IOAM-Namespace and uniquely identify a node within the IOAM-Namespace and associated
associated IOAM-Domain. The procedure to allocate, manage and IOAM-Domain. The procedure to allocate, manage and map the
map the node_ids is beyond the scope of this document. node_ids is beyond the scope of this document.
ingress_if_id and egress_if_id wide: 8-octet field defined as 5.4.2.10. ingress_if_id and egress_if_id wide
follows:
The "ingress_if_id and egress_if_id wide" field is an 8-octet field
which is defined as follows:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id | | ingress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| egress_if_id | | egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ingress_if_id: 4-octet unsigned integer. Interface identifier to ingress_if_id: 4-octet unsigned integer. Interface identifier to
record the ingress interface the packet was received on. record the ingress interface the packet was received on.
egress_if_id: 4-octet unsigned integer. Interface identifier to egress_if_id: 4-octet unsigned integer. Interface identifier to
record the egress interface the packet is forwarded out of. record the egress interface the packet is forwarded out of.
namespace specific data wide: 8-octet field which can be used by the 5.4.2.11. namespace specific data wide
node to add IOAM-Namespace specific data. This represents a
"free-format" 8-octet bit field with its semantics defined in the The "namespace specific data wide" field is an 8-octet field which
context of a specific IOAM-Namespace. can be used by the node to add IOAM-Namespace specific data. This
represents a "free-format" 8-octet bit field with its semantics
defined in the context of a specific IOAM-Namespace.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| namespace specific data ~ | namespace specific data ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ namespace specific data (contd) | ~ namespace specific data (contd) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
buffer occupancy: 4-octet unsigned integer field. This field 5.4.2.12. buffer occupancy
indicates the current status of the occupancy of the common buffer
pool used by a set of queues. The units of this field may be The "buffer occupancy" field is a 4-octet unsigned integer field.
implementation specific. Hence, the units may need to be This field indicates the current status of the occupancy of the
interpreted within the context of an IOAM-Namespace and/or node-id common buffer pool used by a set of queues. The units of this field
if used. The authors acknowledge that in some operational cases are implementation specific. Hence, the units are interpreted within
there is a need for the units to be consistent across a packet the context of an IOAM-Namespace and/or node-id if used. The authors
path through the network, hence recommend the implementations to acknowledge that in some operational cases there is a need for the
use standard unit such as Bytes. units to be consistent across a packet path through the network,
hence RECOMMEND the implementations to use standard units such as
Bytes.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| buffer occupancy | | buffer occupancy |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Checksum Complement: 4-octet node data which contains a 4-octet 5.4.2.13. Opaque State Snapshot
Checksum Complement field. The Checksum Complement is useful when
IOAM is transported over encapsulations that make use of a UDP
transport, such as VXLAN-GPE or Geneve. Without the Checksum
Complement, nodes adding IOAM node data must update the UDP
Checksum field. When the Checksum Complement is present, an IOAM
encapsulating node or IOAM transit node adding node data MUST
carry out one of the following two alternatives in order to
maintain the correctness of the UDP Checksum value:
1. Recompute the UDP Checksum field.
2. Use the Checksum Complement to make a checksum-neutral update
in the UDP payload; the Checksum Complement is assigned a
value that complements the rest of the node data fields that
were added by the current node, causing the existing UDP
Checksum field to remain correct.
IOAM decapsulating nodes MUST recompute the UDP Checksum field,
since they do not know whether previous hops modified the UDP
Checksum field or the Checksum Complement field.
Checksum Complement fields are used in a similar manner in
[RFC7820] and [RFC7821].
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum Complement |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Opaque State Snapshot: Opaque State Snapshot is a variable length The "Opaque State Snapshot" is a variable length field and follows
field and immediately follows the fixed length IOAM-Data-Fields the fixed length IOAM-Data-Fields defined above. It allows the
defined above. It allows the network element to store an network element to store an arbitrary state in the node data field,
arbitrary state in the node data field, without a pre-defined without a pre-defined schema. The schema is to be defined within the
schema. The schema is to be defined within the context of an context of an IOAM-Namespace. The schema needs to be made known to
IOAM-Namespace. The schema needs to be made known to the analyzer the analyzer by some out-of-band mechanism. The specification of
by some out-of-band mechanism. The specification of this this mechanism is beyond the scope of this document. A 24-bit
mechanism is beyond the scope of this document. A 24-bit "Schema "Schema Id" field, interpreted within the context of an IOAM-
Id" field, interpreted within the context of an IOAM-Namespace, Namespace, indicates which particular schema is used, and has to be
indicates which particular schema is used, and should be configured on the network element by the operator.
configured on the network element by the operator.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Schema ID | | Length | Schema ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
| | | |
| Opaque data | | Opaque data |
~ ~ ~ ~
. . . .
. . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Length: 1-octet unsigned integer. It is the length in multiples
of 4-octets of the Opaque data field that follows Schema Id.
Schema ID: 3-octet unsigned integer identifying the schema of Length: 1-octet unsigned integer. It is the length in multiples of
Opaque data. 4-octets of the Opaque data field that follows Schema Id.
Opaque data: Variable length field. This field is interpreted as Schema ID: 3-octet unsigned integer identifying the schema of Opaque
specified by the schema identified by the Schema ID. data.
When this field is part of the data field but a node populating Opaque data: Variable length field. This field is interpreted as
the field has no opaque state data to report, the Length must be specified by the schema identified by the Schema ID.
set to 0 and the Schema ID must be set to 0xFFFFFF to mean no
schema.
4.4.3. Examples of IOAM node data When this field is part of the data field but a node populating the
field has no opaque state data to report, the Length MUST be set to 0
and the Schema ID MUST be set to 0xFFFFFF to mean no schema.
5.4.3. Examples of IOAM node data
An entry in the "node data list" array can have different formats, An entry in the "node data list" array can have different formats,
following the needs of the deployment. Some deployments might only following the needs of the deployment. Some deployments might only
be interested in recording the node identifiers, whereas others might be interested in recording the node identifiers, whereas others might
be interested in recording node identifier and timestamp. The be interested in recording node identifier and timestamp. The
section provides example entries of the "node data list". section provides example entries of the "node data list".
0xD40000: IOAM-Trace-Type is 0xD40000 (0b110101000000000000000000) 0xD40000: IOAM-Trace-Type is 0xD40000 (0b110101000000000000000000)
then the format of node data is: then the format of node data is:
skipping to change at page 24, line 25 skipping to change at page 25, line 25
| Length | Schema Id | | Length | Schema Id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
| | | |
| Opaque data | | Opaque data |
~ ~ ~ ~
. . . .
. . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.5. IOAM Proof of Transit Option-Type 5.5. IOAM Proof of Transit Option-Type
IOAM Proof of Transit Option-Type is to support path or service IOAM Proof of Transit Option-Type is to support path or service
function chain [RFC7665] verification use cases. Proof-of-transit function chain [RFC7665] verification use cases. Proof-of-transit
uses methods like nested hashing or nested encryption of the IOAM leverages mechanisms like Shamir's Secret Sharing Schema (SSSS)
data or mechanisms such as Shamir's Secret Sharing Schema (SSSS). [SSS]. For further information on Proof-of-transit, please refer to
While details on how the IOAM data for the proof of transit option is [I-D.ietf-sfc-proof-of-transit]. While details on how the IOAM data
processed at IOAM encapsulating, decapsulating and transit nodes are for the Proof-of-transit option is processed at IOAM encapsulating,
outside the scope of the document, all of these approaches share the decapsulating and transit nodes are outside the scope of the
need to uniquely identify a packet as well as iteratively operate on document, all of these approaches share the need to uniquely identify
a set of information that is handed from node to node. a packet as well as iteratively operate on a set of information that
Correspondingly, two pieces of information are added as IOAM-Data- is handed from node to node. Correspondingly, two pieces of
Fields to the packet: information are added as IOAM-Data-Fields to the packet:
o Random: Unique identifier for the packet (e.g., 64-bits allow for o Random: Unique identifier for the packet (e.g., 64-bits allow for
the unique identification of 2^64 packets). the unique identification of 2^64 packets).
o Cumulative: Information which is handed from node to node and o Cumulative: Information which is handed from node to node and
updated by every node according to a verification algorithm. updated by every node according to a verification algorithm.
The IOAM Proof of Transit Option-Type consist of a fixed size "IOAM The IOAM Proof-of-Transit Option-Type consist of a fixed size "IOAM
proof of transit option header" and "IOAM proof of transit option proof of transit option header" and "IOAM proof of transit option
data fields": data fields":
IOAM proof of transit option header: IOAM proof of transit option header:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID |IOAM POT Type | IOAM POT flags| | Namespace-ID |IOAM POT Type | IOAM POT flags|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 25, line 35 skipping to change at page 26, line 35
Namespace-ID value that does not match any Namespace-ID the node Namespace-ID value that does not match any Namespace-ID the node
is configured to operate on, the node MUST NOT change the contents is configured to operate on, the node MUST NOT change the contents
of the IOAM-Data-Fields. of the IOAM-Data-Fields.
IOAM POT Type: 8-bit identifier of a particular POT variant that IOAM POT Type: 8-bit identifier of a particular POT variant that
specifies the POT data that is included. This document defines specifies the POT data that is included. This document defines
POT Type 0: POT Type 0:
0: POT data is a 16 Octet field as described below. 0: POT data is a 16 Octet field as described below.
If a node receives an IOAM POT Type value that it does not
understand, the node MUST NOT change the contents of the IOAM-
Data-Fields.
IOAM POT flags: 8-bit. Following flags are defined: IOAM POT flags: 8-bit. Following flags are defined:
Bit 0 "Profile-to-use" (P-bit) (most significant bit). For IOAM Bit 0 "Profile-to-use" (P-bit) (most significant bit). For IOAM
POT types that use a maximum of two profiles to drive POT types that use a maximum of two profiles to drive
computation, indicates which POT-profile is used. The two computation, indicates which POT-profile is used. The two
profiles are numbered 0, 1. profiles are numbered 0, 1.
Bit 1-7 Reserved: Must be set to zero upon transmission and Bit 1-7 Reserved: MUST be set to zero upon transmission and
ignored upon receipt. ignored upon receipt.
POT Option data: Variable-length field. The type of which is POT Option data: Variable-length field. The type of which is
determined by the IOAM-POT-Type. determined by the IOAM-POT-Type.
4.5.1. IOAM Proof of Transit Type 0 5.5.1. IOAM Proof of Transit Type 0
IOAM proof of transit option of IOAM POT Type 0: IOAM proof of transit option of IOAM POT Type 0:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID |IOAM POT Type=0|P|R R R R R R R| | Namespace-ID |IOAM POT Type=0|P|R R R R R R R|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
| Random | | | Random | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ P +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ P
skipping to change at page 27, line 8 skipping to change at page 28, line 8
Random: 64-bit Per packet Random number. Random: 64-bit Per packet Random number.
Cumulative: 64-bit Cumulative that is updated at specific nodes by Cumulative: 64-bit Cumulative that is updated at specific nodes by
processing per packet Random number field and configured processing per packet Random number field and configured
parameters. parameters.
Note: Larger or smaller sizes of "Random" and "Cumulative" data are Note: Larger or smaller sizes of "Random" and "Cumulative" data are
feasible and could be required for certain deployments (e.g. in case feasible and could be required for certain deployments (e.g. in case
of space constraints in the encapsulation protocols used). Future of space constraints in the encapsulation protocols used). Future
documents may address different sizes of data for "proof of transit". documents could introduce different sizes of data for "proof of
transit".
4.6. IOAM Edge-to-Edge Option-Type 5.6. IOAM Edge-to-Edge Option-Type
The IOAM Edge-to-Edge Option-Type is to carry data that is added by The IOAM Edge-to-Edge Option-Type is to carry data that is added by
the IOAM encapsulating node and interpreted by IOAM decapsulating the IOAM encapsulating node and interpreted by IOAM decapsulating
node. The IOAM transit nodes MAY process the data but MUST NOT node. The IOAM transit nodes MAY process the data but MUST NOT
modify it. modify it.
The IOAM Edge-to-Edge Option-Type consist of a fixed size "IOAM Edge- The IOAM Edge-to-Edge Option-Type consist of a fixed size "IOAM Edge-
to-Edge Option-Type header" and "IOAM Edge-to-Edge Option-Type data to-Edge Option-Type header" and "IOAM Edge-to-Edge Option-Type data
fields": fields":
skipping to change at page 28, line 27 skipping to change at page 29, line 30
Bit 2 When set indicates presence of timestamp seconds, Bit 2 When set indicates presence of timestamp seconds,
representing the time at which the packet entered the representing the time at which the packet entered the
IOAM domain. Within the IOAM encapsulating node, the IOAM domain. Within the IOAM encapsulating node, the
time that the timestamp is retrieved can depend on the time that the timestamp is retrieved can depend on the
implementation. Some possibilities are: 1) the time at implementation. Some possibilities are: 1) the time at
which the packet was received by the node, 2) the time at which the packet was received by the node, 2) the time at
which the packet was transmitted by the node, 3) when a which the packet was transmitted by the node, 3) when a
tunnel encapsulation is used, the point at which the tunnel encapsulation is used, the point at which the
packet is encapsulated into the tunnel. Each packet is encapsulated into the tunnel. Each
implementation should document when the E2E timestamp implementation has to document when the E2E timestamp
that is going to be put in the packet is retrieved. This that is going to be put in the packet is retrieved. This
4-octet field has three possible formats; based on either 4-octet field has three possible formats; based on either
PTP [IEEE1588v2], NTP [RFC5905], or POSIX [POSIX]. The PTP [IEEE1588v2], NTP [RFC5905], or POSIX [POSIX]. The
three timestamp formats are specified in Section 5. In three timestamp formats are specified in Section 6. In
all three cases, the Timestamp Seconds field contains the all three cases, the Timestamp Seconds field contains the
32 most significant bits of the timestamp format that is 32 most significant bits of the timestamp format that is
specified in Section 5. If a node is not capable of specified in Section 6. If a node is not capable of
populating this field, it assigns the value 0xFFFFFFFF. populating this field, it assigns the value 0xFFFFFFFF.
Note that this is a legitimate value that is valid for 1 Note that this is a legitimate value that is valid for 1
second in approximately 136 years; the analyzer should second in approximately 136 years; the analyzer has to
correlate several packets or compare the timestamp value correlate several packets or compare the timestamp value
to its own time-of-day in order to detect the error to its own time-of-day in order to detect the error
indication. indication.
Bit 3 When set indicates presence of timestamp subseconds, Bit 3 When set indicates presence of timestamp subseconds,
representing the time at which the packet entered the representing the time at which the packet entered the
IOAM domain. This 4-octet field has three possible IOAM domain. This 4-octet field has three possible
formats; based on either PTP [IEEE1588v2], NTP [RFC5905], formats; based on either PTP [IEEE1588v2], NTP [RFC5905],
or POSIX [POSIX]. The three timestamp formats are or POSIX [POSIX]. The three timestamp formats are
specified in Section 5. In all three cases, the specified in Section 6. In all three cases, the
Timestamp Subseconds field contains the 32 least Timestamp Subseconds field contains the 32 least
significant bits of the timestamp format that is significant bits of the timestamp format that is
specified in Section 5. If a node is not capable of specified in Section 6. If a node is not capable of
populating this field, it assigns the value 0xFFFFFFFF. populating this field, it assigns the value 0xFFFFFFFF.
Note that this is a legitimate value in the NTP format, Note that this is a legitimate value in the NTP format,
valid for approximately 233 picoseconds in every second. valid for approximately 233 picoseconds in every second.
If the NTP format is used the analyzer should correlate If the NTP format is used the analyzer has to correlate
several packets in order to detect the error indication. several packets in order to detect the error indication.
Bit 4-15 Undefined. An IOAM encapsulating node Must set the value Bit 4-15 Undefined. An IOAM encapsulating node MUST set the value
of these bits to zero upon transmission and ignore upon of these bits to zero upon transmission and ignore upon
receipt. receipt.
E2E Option data: Variable-length field. The type of which is E2E Option data: Variable-length field. The type of which is
determined by the IOAM-E2E-Type. determined by the IOAM-E2E-Type.
5. Timestamp Formats 6. Timestamp Formats
The IOAM-Data-Fields include a timestamp field which is represented The IOAM-Data-Fields include a timestamp field which is represented
in one of three possible timestamp formats. It is assumed that the in one of three possible timestamp formats. It is assumed that the
management plane is responsible for determining which timestamp management plane is responsible for determining which timestamp
format is used. format is used.
5.1. PTP Truncated Timestamp Format 6.1. PTP Truncated Timestamp Format
The Precision Time Protocol (PTP) [IEEE1588v2] uses an 80-bit The Precision Time Protocol (PTP) [IEEE1588v2] uses an 80-bit
timestamp format. The truncated timestamp format is a 64-bit field, timestamp format. The truncated timestamp format is a 64-bit field,
which is the 64 least significant bits of the 80-bit PTP timestamp. which is the 64 least significant bits of the 80-bit PTP timestamp.
The PTP truncated format is specified in Section 4.3 of The PTP truncated format is specified in Section 4.3 of
[I-D.ietf-ntp-packet-timestamps], and the details are presented below [I-D.ietf-ntp-packet-timestamps], and the details are presented below
for the sake of completeness. for the sake of completeness.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
skipping to change at page 30, line 30 skipping to change at page 31, line 32
The resolution is 1 nanosecond. The resolution is 1 nanosecond.
Wraparound: Wraparound:
This time format wraps around every 2^32 seconds, which is roughly This time format wraps around every 2^32 seconds, which is roughly
136 years. The next wraparound will occur in the year 2106. 136 years. The next wraparound will occur in the year 2106.
Synchronization Aspects: Synchronization Aspects:
It is assumed that nodes that run this protocol are synchronized It is assumed that nodes that run this protocol are synchronized
among themselves. Nodes may be synchronized to a global reference among themselves. Nodes MAY be synchronized to a global reference
time. Note that if PTP [IEEE1588v2] is used for synchronization, time. Note that if PTP [IEEE1588v2] is used for synchronization,
the timestamp may be derived from the PTP-synchronized clock, the timestamp MAY be derived from the PTP-synchronized clock,
allowing the timestamp to be measured with respect to the clock of allowing the timestamp to be measured with respect to the clock of
an PTP Grandmaster clock. an PTP Grandmaster clock.
The PTP truncated timestamp format is not affected by leap The PTP truncated timestamp format is not affected by leap
seconds. seconds.
5.2. NTP 64-bit Timestamp Format 6.2. NTP 64-bit Timestamp Format
The Network Time Protocol (NTP) [RFC5905] timestamp format is 64 bits The Network Time Protocol (NTP) [RFC5905] timestamp format is 64 bits
long. This format is specified in Section 4.2.1 of long. This format is specified in Section 4.2.1 of
[I-D.ietf-ntp-packet-timestamps], and the details are presented below [I-D.ietf-ntp-packet-timestamps], and the details are presented below
for the sake of completeness. for the sake of completeness.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Seconds | | Seconds |
skipping to change at page 31, line 48 skipping to change at page 32, line 48
The resolution is 2^(-32) seconds. The resolution is 2^(-32) seconds.
Wraparound: Wraparound:
This time format wraps around every 2^32 seconds, which is roughly This time format wraps around every 2^32 seconds, which is roughly
136 years. The next wraparound will occur in the year 2036. 136 years. The next wraparound will occur in the year 2036.
Synchronization Aspects: Synchronization Aspects:
Nodes that use this timestamp format will typically be Nodes that use this timestamp format will typically be
synchronized to UTC using NTP [RFC5905]. Thus, the timestamp may synchronized to UTC using NTP [RFC5905]. Thus, the timestamp MAY
be derived from the NTP-synchronized clock, allowing the timestamp be derived from the NTP-synchronized clock, allowing the timestamp
to be measured with respect to the clock of an NTP server. to be measured with respect to the clock of an NTP server.
The NTP timestamp format is affected by leap seconds; it The NTP timestamp format is affected by leap seconds; it
represents the number of seconds since the epoch minus the number represents the number of seconds since the epoch minus the number
of leap seconds that have occurred since the epoch. The value of of leap seconds that have occurred since the epoch. The value of
a timestamp during or slightly after a leap second may be a timestamp during or slightly after a leap second could be
temporarily inaccurate. temporarily inaccurate.
5.3. POSIX-based Timestamp Format 6.3. POSIX-based Timestamp Format
This timestamp format is based on the POSIX time format [POSIX]. The This timestamp format is based on the POSIX time format [POSIX]. The
detailed specification of the timestamp format used in this document detailed specification of the timestamp format used in this document
is presented below. is presented below.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Seconds | | Seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 33, line 12 skipping to change at page 34, line 12
The resolution is 1 microsecond. The resolution is 1 microsecond.
Wraparound: Wraparound:
This time format wraps around every 2^32 seconds, which is roughly This time format wraps around every 2^32 seconds, which is roughly
136 years. The next wraparound will occur in the year 2106. 136 years. The next wraparound will occur in the year 2106.
Synchronization Aspects: Synchronization Aspects:
It is assumed that nodes that use this timestamp format run Linux It is assumed that nodes that use this timestamp format run the
operating system, and hence use the POSIX time. In some cases Linux operating system, and hence use the POSIX time. In some
nodes may be synchronized to UTC using a synchronization mechanism cases nodes MAY be synchronized to UTC using a synchronization
that is outside the scope of this document, such as NTP [RFC5905]. mechanism that is outside the scope of this document, such as NTP
Thus, the timestamp may be derived from the NTP-synchronized [RFC5905]. Thus, the timestamp MAY be derived from the NTP-
clock, allowing the timestamp to be measured with respect to the synchronized clock, allowing the timestamp to be measured with
clock of an NTP server. respect to the clock of an NTP server.
The POSIX-based timestamp format is affected by leap seconds; it The POSIX-based timestamp format is affected by leap seconds; it
represents the number of seconds since the epoch minus the number represents the number of seconds since the epoch minus the number
of leap seconds that have occurred since the epoch. The value of of leap seconds that have occurred since the epoch. The value of
a timestamp during or slightly after a leap second may be a timestamp during or slightly after a leap second could be
temporarily inaccurate. temporarily inaccurate.
6. IOAM Data Export 7. IOAM Data Export
IOAM nodes collect information for packets traversing a domain that IOAM nodes collect information for packets traversing a domain that
supports IOAM. IOAM decapsulating nodes as well as IOAM transit supports IOAM. IOAM decapsulating nodes as well as IOAM transit
nodes can choose to retrieve IOAM information from the packet, nodes can choose to retrieve IOAM information from the packet,
process the information further and export the information using process the information further and export the information using
e.g., IPFIX. The mechanisms and associated data formats for e.g., IPFIX. The mechanisms and associated data formats for
exporting IOAM data is outside the scope of this document. exporting IOAM data is outside the scope of this document.
Raw data export of IOAM data using IPFIX is discussed in Raw data export of IOAM data using IPFIX is discussed in
[I-D.spiegel-ippm-ioam-rawexport]. [I-D.spiegel-ippm-ioam-rawexport].
7. IANA Considerations 8. IANA Considerations
This document requests the following IANA Actions. This document requests the following IANA Actions.
7.1. Creation of a new In-Situ OAM Protocol Parameters Registry (IOAM) IANA is requested to define a registry group named "In-Situ OAM
Protocol Parameters IANA registry (IOAM) Protocol Parameters".
IANA is requested to create a new protocol registry for "In-Situ OAM This group will include the following registries:
(IOAM) Protocol Parameters". This is the common registry that will
include registrations for all IOAM-Namespaces. Each Registry, whose
names are listed below:
IOAM Option-Type IOAM Option-Type
IOAM Trace-Type IOAM Trace-Type
IOAM Trace-Flags
IOAM Trace-Flags
IOAM POT-Type IOAM POT-Type
IOAM POT-Flags IOAM POT-Flags
IOAM E2E-Type IOAM E2E-Type
IOAM Namespace-ID IOAM Namespace-ID
will contain the current set of possibilities defined in this New registries in this group can be created via RFC Required process
document. New registries in this name space are created via RFC as per [RFC8126].
Required process as per [RFC8126].
The subsequent sub-sections detail the registries herein contained. The subsequent sub-sections detail the registries herein contained.
7.2. IOAM Option-Type Registry 8.1. IOAM Option-Type Registry
This registry defines 128 code points for the IOAM Option-Type field This registry defines 128 code points for the IOAM Option-Type field
for identifying IOAM Option-Types as explained in Section 4. The for identifying IOAM Option-Types as explained in Section 5. The
following code points are defined in this draft: following code points are defined in this draft:
0 IOAM Pre-allocated Trace Option-Type 0 IOAM Pre-allocated Trace Option-Type
1 IOAM Incremental Trace Option-Type 1 IOAM Incremental Trace Option-Type
2 IOAM POT Option-Type 2 IOAM POT Option-Type
3 IOAM E2E Option-Type 3 IOAM E2E Option-Type
4 - 127 are available for assignment via RFC Required process as per 4 - 127 are available for assignment via RFC Required process as per
[RFC8126]. [RFC8126].
7.3. IOAM Trace-Type Registry 8.2. IOAM Trace-Type Registry
This registry defines code point for each bit in the 24-bit IOAM- This registry defines code point for each bit in the 24-bit IOAM-
Trace-Type field for Pre-allocated trace option and Incremental trace Trace-Type field for Pre-allocated trace option and Incremental trace
option defined in Section 4.4. The meaning of Bits 0 - 11 for trace option defined in Section 5.4. The meaning of Bits 0 - 11 for trace
type are defined in this document in Paragraph 5 of Section 4.4.1: type are defined in this document in Paragraph 5 of Section 5.4.1:
Bit 0 hop_Lim and node_id in short format Bit 0 hop_Lim and node_id in short format
Bit 1 ingress_if_id and egress_if_id in short format Bit 1 ingress_if_id and egress_if_id in short format
Bit 2 timestamp seconds Bit 2 timestamp seconds
Bit 3 timestamp subseconds Bit 3 timestamp subseconds
Bit 4 transit delay Bit 4 transit delay
Bit 5 namespace specific data in short format Bit 5 namespace specific data in short format
Bit 6 queue depth Bit 6 queue depth
Bit 7 checksum complement Bit 7 checksum complement
Bit 8 hop_Lim and node_id in wide format Bit 8 hop_Lim and node_id in wide format
Bit 9 ingress_if_id and egress_if_id in wide format Bit 9 ingress_if_id and egress_if_id in wide format
Bit 10 namespace specific data in wide format Bit 10 namespace specific data in wide format
Bit 11 buffer occupancy Bit 11 buffer occupancy
Bit 22 variable length Opaque State Snapshot Bit 22 variable length Opaque State Snapshot
Bit 23 reserved Bit 23 reserved
The meaning for Bits 12 - 21 are available for assignment via RFC The meaning for Bits 12 - 21 are available for assignment via RFC
Required process as per [RFC8126]. Required process as per [RFC8126].
7.4. IOAM Trace-Flags Registry 8.3. IOAM Trace-Flags Registry
This registry defines code points for each bit in the 4 bit flags for This registry defines code points for each bit in the 4 bit flags for
the Pre-allocated trace option and for the Incremental trace option the Pre-allocated trace option and for the Incremental trace option
defined in Section 4.4. The meaning of Bit 0 (the most significant defined in Section 5.4. The meaning of Bit 0 (the most significant
bit) for trace flags is defined in this document in Paragraph 3 of bit) for trace flags is defined in this document in Paragraph 3 of
Section 4.4.1: Section 5.4.1:
Bit 0 "Overflow" (O-bit) Bit 0 "Overflow" (O-bit)
Bit 1 - 3 are available for assignment via RFC Required process as Bit 1 - 3 are available for assignment via RFC Required process as
per [RFC8126]. per [RFC8126].
7.5. IOAM POT-Type Registry 8.4. IOAM POT-Type Registry
This registry defines 256 code points to define IOAM POT Type for This registry defines 256 code points to define IOAM POT Type for
IOAM proof of transit option Section 4.5. The code point value 0 is IOAM proof of transit option Section 5.5. The code point value 0 is
defined in this document: defined in this document:
0: 16 Octet POT data 0: 16 Octet POT data
1 - 255 are available for assignment via RFC Required process as per 1 - 255 are available for assignment via RFC Required process as per
[RFC8126]. [RFC8126].
7.6. IOAM POT-Flags Registry 8.5. IOAM POT-Flags Registry
This registry defines code points for each bit in the 8 bit flags for This registry defines code points for each bit in the 8 bit flags for
IOAM POT option defined in Section 4.5. The meaning of Bit 0 for IOAM POT option defined in Section 5.5. The meaning of Bit 0 for
IOAM POT flags is defined in this document in Section 4.5: IOAM POT flags is defined in this document in Section 5.5:
Bit 0 "Profile-to-use" (P-bit) Bit 0 "Profile-to-use" (P-bit)
The meaning for Bits 1 - 7 are available for assignment via RFC The meaning for Bits 1 - 7 are available for assignment via RFC
Required process as per [RFC8126]. Required process as per [RFC8126].
7.7. IOAM E2E-Type Registry 8.6. IOAM E2E-Type Registry
This registry defines code points for each bit in the 16 bit IOAM- This registry defines code points for each bit in the 16 bit IOAM-
E2E-Type field for IOAM E2E option Section 4.6. The meaning of Bit 0 E2E-Type field for IOAM E2E option Section 5.6. The meaning of Bit 0
- 3 are defined in this document: - 3 are defined in this document:
Bit 0 64-bit sequence number Bit 0 64-bit sequence number
Bit 1 32-bit sequence number Bit 1 32-bit sequence number
Bit 2 timestamp seconds Bit 2 timestamp seconds
Bit 3 timestamp subseconds Bit 3 timestamp subseconds
The meaning of Bits 4 - 15 are available for assignment via RFC The meaning of Bits 4 - 15 are available for assignment via RFC
Required process as per [RFC8126]. Required process as per [RFC8126].
7.8. IOAM Namespace-ID Registry 8.7. IOAM Namespace-ID Registry
IANA is requested to set up an "IOAM Namespace-ID Registry", IANA is requested to set up an "IOAM Namespace-ID Registry",
containing 16-bit values. The meaning of Bit 0 is defined in this containing 16-bit values. The meaning of Bit 0 is defined in this
document. IANA is requested to reserve the values 0x0001 to 0x7FFF document. IANA is requested to reserve the values 0x0001 to 0x7FFF
for private use (managed by operators), as specified in Section 4.3 for private use (managed by operators), as specified in Section 5.3
of the current document. Registry entries for the values 0x8000 to of the current document. Registry entries for the values 0x8000 to
0xFFFF are to be assigned via the "Expert Review" policy defined in 0xFFFF are to be assigned via the "Expert Review" policy defined in
[RFC8126]. [RFC8126]. Upon a new allocation request, the responsible AD will
appoint a designated expert, who will review the allocation request.
The expert will post the request on the IPPM mailing list, and
possibly on other relevant mailing lists, to allow for community
feedback. Based on the review, the expert will either approve or
deny the request. The intention is that any allocation will be
accompanied by a published RFC. But in order to allow for the
allocation of values prior to the RFC being approved for publication,
the designated expert can approve allocations once it seems clear
that an RFC will be published.
0: default namespace (known to all IOAM nodes) 0: default namespace (known to all IOAM nodes)
0x0001 - 0x7FFF: reserved for private use 0x0001 - 0x7FFF: reserved for private use
0x8000 - 0xFFFF: unassigned 0x8000 - 0xFFFF: unassigned
8. Security Considerations 9. Management and Deployment Considerations
This document defines the structure and use of IOAM data fields.
This document does not define the encapsulation of IOAM data fields
into different protocols. Management and deployment aspects for IOAM
have to be considered within the context of the protocol IOAM data
fields are encapsulated into and as such, are out of scope for this
document. For a discussion of IOAM deployment, please also refer to
[I-D.brockners-opsawg-ioam-deployment], which outlines a framework
for IOAM deployment and provides best current practices.
10. Security Considerations
As discussed in [RFC7276], a successful attack on an OAM protocol in As discussed in [RFC7276], a successful attack on an OAM protocol in
general, and specifically on IOAM, can prevent the detection of general, and specifically on IOAM, can prevent the detection of
failures or anomalies, or create a false illusion of nonexistent failures or anomalies, or create a false illusion of nonexistent
ones. In particular, these threats are applicable by compromising ones. In particular, these threats are applicable by compromising
the integrity of IOAM data, either by maliciously modifying IOAM the integrity of IOAM data, either by maliciously modifying IOAM
options in transit, or by injecting packets with maliciously options in transit, or by injecting packets with maliciously
generated IOAM options generated IOAM options
The Proof of Transit Option-Type (Section Section 4.5) is used for The Proof of Transit Option-Type (Section Section 5.5) is used for
verifying the path of data packets. The security considerations of verifying the path of data packets. The security considerations of
POT are further discussed in [I-D.ietf-sfc-proof-of-transit]. POT are further discussed in [I-D.ietf-sfc-proof-of-transit].
From a confidentiality perspective, although IOAM options do not From a confidentiality perspective, although IOAM options do not
contain user data, they can be used for network reconnaissance, contain user data, they can be used for network reconnaissance,
allowing attackers to collect information about network paths, allowing attackers to collect information about network paths,
performance, queue states, buffer occupancy and other information. performance, queue states, buffer occupancy and other information.
Moreover, if IOAM data leaks from the IOAM domain it may enable Moreover, if IOAM data leaks from the IOAM domain it could enable
reconnaissance beyond the scope of the IOAM domain. Note that in reconnaissance beyond the scope of the IOAM domain. Note that in
case IOAM is used in "Direct Exporting" mode case IOAM is used in "Direct Exporting" mode
[I-D.ioamteam-ippm-ioam-direct-export], the IOAM related trace [I-D.ioamteam-ippm-ioam-direct-export], the IOAM related trace
information would not be available in the customer data packets, but information would not be available in the customer data packets, but
would trigger export of packet related IOAM information at every would trigger export of packet related IOAM information at every
node, thus restricting the potential threat to the management plane node, thus restricting the potential threat to the management plane
and mitigating the leakage threat. IOAM data exporting and the way and mitigating the leakage threat. IOAM data exporting and the way
it is secured is outside the scope of this document. it is secured is outside the scope of this document.
IOAM can be used as a means for implementing Denial of Service (DoS) IOAM can be used as a means for implementing Denial of Service (DoS)
attacks, or for amplifying them. For example, a malicious attacker attacks, or for amplifying them. For example, a malicious attacker
can add an IOAM header to packets in order to consume the resources can add an IOAM header to packets in order to consume the resources
of network devices that take part in IOAM or entities that receive, of network devices that take part in IOAM or entities that receive,
collect or analyze the IOAM data. Another example is a packet length collect or analyze the IOAM data. Another example is a packet length
attack, in which an attacker pushes headers associated with IOAM attack, in which an attacker pushes headers associated with IOAM
Option-Types into data packets, causing these packets to be increased Option-Types into data packets, causing these packets to be increased
beyond the MTU size, resulting in fragmentation or in packet drops. beyond the MTU size, resulting in fragmentation or in packet drops.
Since IOAM options may include timestamps, if network devices use Since IOAM options can include timestamps, if network devices use
synchronization protocols then any attack on the time protocol synchronization protocols then any attack on the time protocol
[RFC7384] can compromise the integrity of the timestamp-related data [RFC7384] can compromise the integrity of the timestamp-related data
fields. fields.
At the management plane, attacks may be implemented by misconfiguring At the management plane, attacks can be set up by misconfiguring or
or by maliciously configuring IOAM-enabled nodes in a way that by maliciously configuring IOAM-enabled nodes in a way that enables
enables other attacks. Thus, IOAM configuration should be secured in other attacks. Thus, IOAM configuration has to be secured in a way
a way that authenticates authorized users and verifies the integrity that authenticates authorized users and verifies the integrity of
of configuration procedures. configuration procedures.
The current document does not define a specific IOAM encapsulation. The current document does not define a specific IOAM encapsulation.
It should be noted that some IOAM encapsulation types may introduce It has to be noted that some IOAM encapsulation types can introduce
specific security considerations. A specification that defines an specific security considerations. A specification that defines an
IOAM encapsulation is expected to address the respective IOAM encapsulation is expected to address the respective
encapsulation-specific security considerations. encapsulation-specific security considerations.
Notably, in most cases IOAM is expected to be deployed in specific Notably, in most cases IOAM is expected to be deployed in specific
network domains, thus confining the potential attack vectors to network domains, thus confining the potential attack vectors to
within the network domain. A limited administrative domain provides within the network domain. A limited administrative domain provides
the operator with the means to select, monitor, and control the the operator with the means to select, monitor, and control the
access of all the network devices, making these devices trusted by access of all the network devices, making these devices trusted by
the operator. Indeed, in order to limit the scope of threats the operator. Indeed, in order to limit the scope of threats
mentioned above to within the current network domain the network mentioned above to within the current network domain the network
operator is expected to enforce policies that prevent IOAM traffic operator is expected to enforce policies that prevent IOAM traffic
from leaking outside of the IOAM domain, and prevent IOAM data from from leaking outside of the IOAM domain, and prevent IOAM data from
outside the domain to be processed and used within the domain. outside the domain to be processed and used within the domain.
The security considerations of a system that deploys IOAM, much like The security considerations of a system that deploys IOAM, much like
any system, should be reviewed on a per-deployment-scenario basis, any system, has to be reviewed on a per-deployment-scenario basis,
based on a systems-specific threat analysis, which may lead to based on a systems-specific threat analysis, which can lead to
specific security solutions that are beyond the scope of the current specific security solutions that are beyond the scope of the current
document. For example, in an IOAM deployment that is not confined to document. For example, in an IOAM deployment that is not confined to
a single LAN, but spans multiple inter-connected sites, the inter- a single LAN, but spans multiple inter-connected sites, the inter-
site links may be secured (e.g., by IPsec) in order to avoid external site links can be secured (e.g., by IPsec) in order to avoid external
threats. threats.
9. Acknowledgements 11. Acknowledgements
The authors would like to thank Eric Vyncke, Nalini Elkins, Srihari The authors would like to thank Eric Vyncke, Nalini Elkins, Srihari
Raghavan, Ranganathan T S, Karthik Babu Harichandra Babu, Akshaya Raghavan, Ranganathan T S, Karthik Babu Harichandra Babu, Akshaya
Nadahalli, LJ Wobker, Erik Nordmark, Vengada Prasad Govindan, Andrew Nadahalli, LJ Wobker, Erik Nordmark, Vengada Prasad Govindan, Andrew
Yourtchenko, Aviv Kfir, Tianran Zhou and Zhenbin (Robin) for the Yourtchenko, Aviv Kfir, Tianran Zhou and Zhenbin (Robin) for the
comments and advice. comments and advice.
This document leverages and builds on top of several concepts This document leverages and builds on top of several concepts
described in [I-D.kitamura-ipv6-record-route]. The authors would described in [I-D.kitamura-ipv6-record-route]. The authors would
like to acknowledge the work done by the author Hiroshi Kitamura and like to acknowledge the work done by the author Hiroshi Kitamura and
people involved in writing it. people involved in writing it.
The authors would like to gracefully acknowledge useful review and The authors would like to gracefully acknowledge useful review and
insightful comments received from Joe Clarke, Al Morton, Tom Herbert, insightful comments received from Joe Clarke, Al Morton, Tom Herbert,
Haoyu Song, Mickey Spiegel and Barak Gafni. Haoyu Song, Mickey Spiegel and Barak Gafni.
10. References 12. References
10.1. Normative References
12.1. Normative References
[IEEE1588v2] [IEEE1588v2]
Institute of Electrical and Electronics Engineers, "IEEE Institute of Electrical and Electronics Engineers, "IEEE
Std 1588-2008 - IEEE Standard for a Precision Clock Std 1588-2008 - IEEE Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and Synchronization Protocol for Networked Measurement and
Control Systems", IEEE Std 1588-2008, 2008, Control Systems", IEEE Std 1588-2008, 2008,
<http://standards.ieee.org/findstds/ <http://standards.ieee.org/findstds/
standard/1588-2008.html>. standard/1588-2008.html>.
[POSIX] Institute of Electrical and Electronics Engineers, "IEEE [POSIX] Institute of Electrical and Electronics Engineers, "IEEE
skipping to change at page 39, line 36 skipping to change at page 40, line 45
[RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch, [RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
"Network Time Protocol Version 4: Protocol and Algorithms "Network Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010, Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
<https://www.rfc-editor.org/info/rfc5905>. <https://www.rfc-editor.org/info/rfc5905>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26, Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017, RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>. <https://www.rfc-editor.org/info/rfc8126>.
10.2. Informative References 12.2. Informative References
[I-D.brockners-opsawg-ioam-deployment]
Brockners, F., Bhandari, S., and d.
daniel.bernier@bell.ca, "In-situ OAM Deployment", draft-
brockners-opsawg-ioam-deployment-01 (work in progress),
March 2020.
[I-D.ietf-ntp-packet-timestamps] [I-D.ietf-ntp-packet-timestamps]
Mizrahi, T., Fabini, J., and A. Morton, "Guidelines for Mizrahi, T., Fabini, J., and A. Morton, "Guidelines for
Defining Packet Timestamps", draft-ietf-ntp-packet- Defining Packet Timestamps", draft-ietf-ntp-packet-
timestamps-08 (work in progress), February 2020. timestamps-09 (work in progress), March 2020.
[I-D.ietf-nvo3-geneve] [I-D.ietf-nvo3-geneve]
Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic
Network Virtualization Encapsulation", draft-ietf- Network Virtualization Encapsulation", draft-ietf-
nvo3-geneve-15 (work in progress), February 2020. nvo3-geneve-16 (work in progress), March 2020.
[I-D.ietf-nvo3-vxlan-gpe] [I-D.ietf-nvo3-vxlan-gpe]
Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol
Extension for VXLAN", draft-ietf-nvo3-vxlan-gpe-09 (work Extension for VXLAN", draft-ietf-nvo3-vxlan-gpe-09 (work
in progress), December 2019. in progress), December 2019.
[I-D.ietf-sfc-proof-of-transit] [I-D.ietf-sfc-proof-of-transit]
Brockners, F., Bhandari, S., Mizrahi, T., Dara, S., and S. Brockners, F., Bhandari, S., Mizrahi, T., Dara, S., and S.
Youell, "Proof of Transit", draft-ietf-sfc-proof-of- Youell, "Proof of Transit", draft-ietf-sfc-proof-of-
transit-04 (work in progress), November 2019. transit-06 (work in progress), June 2020.
[I-D.ioamteam-ippm-ioam-direct-export] [I-D.ioamteam-ippm-ioam-direct-export]
Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F., Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F.,
Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ
OAM Direct Exporting", draft-ioamteam-ippm-ioam-direct- OAM Direct Exporting", draft-ioamteam-ippm-ioam-direct-
export-00 (work in progress), October 2019. export-00 (work in progress), October 2019.
[I-D.kitamura-ipv6-record-route] [I-D.kitamura-ipv6-record-route]
Kitamura, H., "Record Route for IPv6 (PR6) Hop-by-Hop Kitamura, H., "Record Route for IPv6 (PR6) Hop-by-Hop
Option Extension", draft-kitamura-ipv6-record-route-00 Option Extension", draft-kitamura-ipv6-record-route-00
(work in progress), November 2000. (work in progress), November 2000.
[I-D.lapukhov-dataplane-probe]
Lapukhov, P. and r. remy@barefootnetworks.com, "Data-plane
probe for in-band telemetry collection", draft-lapukhov-
dataplane-probe-01 (work in progress), June 2016.
[I-D.spiegel-ippm-ioam-rawexport] [I-D.spiegel-ippm-ioam-rawexport]
Spiegel, M., Brockners, F., Bhandari, S., and R. Spiegel, M., Brockners, F., Bhandari, S., and R.
Sivakolundu, "In-situ OAM raw data export with IPFIX", Sivakolundu, "In-situ OAM raw data export with IPFIX",
draft-spiegel-ippm-ioam-rawexport-02 (work in progress), draft-spiegel-ippm-ioam-rawexport-03 (work in progress),
July 2019. March 2020.
[RFC7276] Mizrahi, T., Sprecher, N., Bellagamba, E., and Y. [RFC7276] Mizrahi, T., Sprecher, N., Bellagamba, E., and Y.
Weingarten, "An Overview of Operations, Administration, Weingarten, "An Overview of Operations, Administration,
and Maintenance (OAM) Tools", RFC 7276, and Maintenance (OAM) Tools", RFC 7276,
DOI 10.17487/RFC7276, June 2014, DOI 10.17487/RFC7276, June 2014,
<https://www.rfc-editor.org/info/rfc7276>. <https://www.rfc-editor.org/info/rfc7276>.
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in [RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384, Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384,
October 2014, <https://www.rfc-editor.org/info/rfc7384>. October 2014, <https://www.rfc-editor.org/info/rfc7384>.
skipping to change at page 41, line 20 skipping to change at page 42, line 29
[RFC7821] Mizrahi, T., "UDP Checksum Complement in the Network Time [RFC7821] Mizrahi, T., "UDP Checksum Complement in the Network Time
Protocol (NTP)", RFC 7821, DOI 10.17487/RFC7821, March Protocol (NTP)", RFC 7821, DOI 10.17487/RFC7821, March
2016, <https://www.rfc-editor.org/info/rfc7821>. 2016, <https://www.rfc-editor.org/info/rfc7821>.
[RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
"Network Service Header (NSH)", RFC 8300, "Network Service Header (NSH)", RFC 8300,
DOI 10.17487/RFC8300, January 2018, DOI 10.17487/RFC8300, January 2018,
<https://www.rfc-editor.org/info/rfc8300>. <https://www.rfc-editor.org/info/rfc8300>.
Authors' Addresses [SSS] Wikipedia, "Shamir's Secret Sharing",
<https://en.wikipedia.org/wiki/Shamir%27s_Secret_Sharing>.
Frank Brockners Contributors' Addresses
Cisco Systems, Inc.
Hansaallee 249, 3rd Floor
DUESSELDORF, NORDRHEIN-WESTFALEN 40549
Germany
Email: fbrockne@cisco.com Carlos Pignataro
Cisco Systems, Inc.
7200-11 Kit Creek Road
Research Triangle Park, NC 27709
United States
Shwetha Bhandari Email: cpignata@cisco.com
Cisco Systems, Inc.
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Email: shwethab@cisco.com Mickey Spiegel
Barefoot Networks, an Intel company
4750 Patrick Henry Drive
Santa Clara, CA 95054
US
Carlos Pignataro Email: mickey.spiegel@intel.com
Cisco Systems, Inc.
7200-11 Kit Creek Road
Research Triangle Park, NC 27709
United States
Email: cpignata@cisco.com Barak Gafni
Mellanox Technologies, Inc.
350 Oakmead Parkway, Suite 100
Sunnyvale, CA 94085
U.S.A.
Hannes Gredler Email: gbarak@mellanox.com
RtBrick Inc.
Email: hannes@rtbrick.com Jennifer Lemon
John Leddy Broadcom
United States 270 Innovation Drive
San Jose, CA 95134
US
Email: john@leddy.net Email: jennifer.lemon@broadcom.com
Stephen Youell Hannes Gredler
JP Morgan Chase RtBrick Inc.
25 Bank Street
London E14 5JP
United Kingdom
Email: stephen.youell@jpmorgan.com Email: hannes@rtbrick.com
Tal Mizrahi John Leddy
Huawei Network.IO Innovation Lab United States
Israel
Email: tal.mizrahi.phd@gmail.com Email: john@leddy.net
David Mozes Stephen Youell
JP Morgan Chase
25 Bank Street
London E14 5JP
United Kingdom
Email: mosesster@gmail.com Email: stephen.youell@jpmorgan.com
Petr Lapukhov David Mozes
Facebook
1 Hacker Way
Menlo Park, CA 94025
US
Email: petr@fb.com Email: mosesster@gmail.com
Remy Chang Petr Lapukhov
Barefoot Networks Facebook
4750 Patrick Henry Drive 1 Hacker Way
Santa Clara, CA 95054 Menlo Park, CA 94025
US US
Email: petr@fb.com
Email: remy@barefootnetworks.com Remy Chang
Daniel Bernier Barefoot Networks
Bell Canada 4750 Patrick Henry Drive
Canada Santa Clara, CA 95054
US
Email: daniel.bernier@bell.ca Email: remy@barefootnetworks.com
Jennifer Lemon Daniel Bernier
Broadcom Bell Canada
270 Innovation Drive Canada
San Jose, CA 95134
US
Email: jennifer.lemon@broadcom.com Email: daniel.bernier@bell.ca
Authors' Addresses
Frank Brockners (editor)
Cisco Systems, Inc.
Hansaallee 249, 3rd Floor
DUESSELDORF, NORDRHEIN-WESTFALEN 40549
Germany
Email: fbrockne@cisco.com
Shwetha Bhandari (editor)
Cisco Systems, Inc.
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Email: shwethab@cisco.com
Tal Mizrahi (editor)
Huawei
8-2 Matam
Haifa 3190501
Israel
Email: tal.mizrahi.phd@gmail.com
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