< draft-ietf-bier-isis-extensions-07.txt   draft-ietf-bier-isis-extensions-08.txt >
Internet Engineering Task Force L. Ginsberg, Ed. Internet Engineering Task Force L. Ginsberg, Ed.
Internet-Draft Cisco Systems Internet-Draft Cisco Systems
Intended status: Standards Track A. Przygienda Intended status: Standards Track A. Przygienda
Expires: August 13, 2018 Juniper Networks Expires: August 26, 2018 Juniper Networks
S. Aldrin S. Aldrin
Google Google
J. Zhang J. Zhang
Juniper Networks, Inc. Juniper Networks, Inc.
February 9, 2018 February 22, 2018
BIER support via ISIS BIER support via ISIS
draft-ietf-bier-isis-extensions-07 draft-ietf-bier-isis-extensions-08
Abstract Abstract
Specification of an ISIS extension to support BIER domains and sub- This document defines ISIS extensions to support multicast forwarding
domains. using the Bit Index Explicit Replication (BIER) architecture.
Requirements Language Requirements Language
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", "NOT RECOMMENDED", "MAY", and
document are to be interpreted as described in RFC 2119 [RFC2119] . "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 13, 2018. This Internet-Draft will expire on August 26, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
4. Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. BIER Domains and Sub-Domains . . . . . . . . . . . . . . 4 4.1. BIER Domains and Sub-Domains . . . . . . . . . . . . . . 5
4.2. Advertising BIER Information . . . . . . . . . . . . . . 4 4.2. Advertising BIER Information . . . . . . . . . . . . . . 5
5. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.1. Multi Topology and Sub-Domain . . . . . . . . . . . . . . 5 5.1. Multi Topology and Sub-Domain . . . . . . . . . . . . . . 5
5.2. Encapsulation . . . . . . . . . . . . . . . . . . . . . . 5 5.2. Label advertisements for MPLS Encapsulation . . . . . . . 6
5.3. BIER Algorithm . . . . . . . . . . . . . . . . . . . . . 5 5.3. BFR-id Advertisements . . . . . . . . . . . . . . . . . . 6
5.4. Label advertisements for MPLS Encapsulation . . . . . . . 6 5.4. Logging Misconfiguration . . . . . . . . . . . . . . . . 6
5.5. BFR-id Advertisements . . . . . . . . . . . . . . . . . . 6 5.5. Flooding Reduction . . . . . . . . . . . . . . . . . . . 6
5.6. Reporting Misconfiguration . . . . . . . . . . . . . . . 6 6. Packet Formats . . . . . . . . . . . . . . . . . . . . . . . 7
5.7. Flooding Reduction . . . . . . . . . . . . . . . . . . . 6 6.1. BIER Info sub-TLV . . . . . . . . . . . . . . . . . . . . 7
6. Packet Formats . . . . . . . . . . . . . . . . . . . . . . . 6 6.2. BIER MPLS Encapsulation sub-sub-TLV . . . . . . . . . . . 8
6.1. BIER Info sub-TLV . . . . . . . . . . . . . . . . . . . . 6 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9
6.2. BIER MPLS Encapsulation sub-sub-TLV . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9
7. Security Considerations . . . . . . . . . . . . . . . . . . . 8 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 9.1. Normative References . . . . . . . . . . . . . . . . . . 9
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 9.2. Informative References . . . . . . . . . . . . . . . . . 10
9.1. Normative References . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
9.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
Bit Index Explicit Replication (BIER) [RFC8279] defines an Bit Index Explicit Replication (BIER) [RFC8279] defines an
architecture where all intended multicast receivers are encoded as architecture where all intended multicast receivers are encoded as
bitmask in the Multicast packet header within different bitmask in the Multicast packet header within different
encapsulations such as [RFC8296]. A router that receives such a encapsulations such as [RFC8296]. A router that receives such a
packet will forward the packet based on the Bit Position in the packet will forward the packet based on the Bit Position in the
packet header towards the receiver(s), following a precomputed tree packet header towards the receiver(s), following a precomputed tree
for each of the bits in the packet. Each receiver is represented by for each of the bits in the packet. Each receiver is represented by
a unique bit in the bitmask. a unique bit in the bitmask.
This document presents necessary extensions to the currently deployed This document presents necessary extensions to the currently deployed
ISIS for IP [RFC1195] protocol to support distribution of information ISIS for IP [RFC1195] protocol to support distribution of information
necessary for operation of BIER domains and sub-domains. This necessary for operation of BIER domains and sub-domains. This
document defines a new TLV to be advertised by every router document defines a new TLV to be advertised by every router
participating in BIER signaling. participating in BIER signaling.
This document defines support for MPLS encapsulation as specified in
[RFC8296]. Support for other encapsulation types is outside the
scope of this document. The use of multiple encapsulation types is
outside the scope of this document.
2. Terminology 2. Terminology
Some of the terminology specified in [RFC8279] is replicated here and Some of the terminology specified in [RFC8279] is replicated here and
extended by necessary definitions: extended by necessary definitions:
BIER: Bit Index Explicit Replication (The overall architecture of BIER: Bit Index Explicit Replication (The overall architecture of
forwarding multicast using a Bit Position). forwarding multicast using a Bit Position).
BIER-OL: BIER Overlay Signaling. (The method for the BFIR to learn BIER-OL: BIER Overlay Signaling. (The method for the BFIR to learn
about BFER's). about BFER's).
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BIER sub-domain: A further distinction within a BIER domain BIER sub-domain: A further distinction within a BIER domain
identified by its unique sub-domain identifier. A BIER sub-domain identified by its unique sub-domain identifier. A BIER sub-domain
can support multiple BitString Lengths. can support multiple BitString Lengths.
BFR-id: An optional, unique identifier for a BFR within a BIER sub- BFR-id: An optional, unique identifier for a BFR within a BIER sub-
domain. domain.
Invalid BFR-id: Unassigned BFR-id. The special value 0 is reserved Invalid BFR-id: Unassigned BFR-id. The special value 0 is reserved
for this purpose. for this purpose.
BAR BIER Algorithm. Algorithm used to calculate nexthops. BAR BIER Algorithm. Used to calculate underlay next hops.
IPA IGP Algorithm. May be used to modify, enhance or replace the
calculation of underlay paths as defined by the BAR value
SPF Shortest Path First routing calculation based on IGP link metric
3. IANA Considerations 3. IANA Considerations
This document adds the following new sub-TLV to the registry of sub- This document adds the following new sub-TLV to the registry of Sub-
TLVs for TLVs 235, 237 [RFC5120] and TLVs 135,236 TLVs for TLVs 135, 235, 236, and 237.
[RFC5305],[RFC5308].
Value: 32 (suggested - to be assigned by IANA) Value: 32 (suggested - to be assigned by IANA)
Name: BIER Info Name: BIER Info
This document also introduces a new registry for sub-sub-TLVs for the This document also introduces a new registry for sub-sub-TLVs for the
BIER Info sub-TLV added above. The registration policy is Expert BIER Info sub-TLV added above. The registration policy is Expert
Review as defined in [RFC8126]. This registry is part of the "IS-IS Review as defined in [RFC8126]. This registry is part of the "IS-IS
TLV Codepoints" registry. The name of the registry is "sub-sub-TLVs TLV Codepoints" registry. The name of the registry is "sub-sub-TLVs
for BIER Info sub-TLV". The defined values are: for BIER Info sub-TLV". The defined values are:
Type Name Type Name
---- ---- ---- ----
1 BIER MPLS Encapsulation 1 BIER MPLS Encapsulation
IANA is requested to set up a registry called "BIER Algorithm
Registry" under category "Bit Index Explicit Replication". The
registration policies [RFC8126] for this registry are:
"Standards Action" for values 0-127
"Specification Required" for values 128-240
"Experimental Use" for values 240-254"
The initial values in the BIER Algorithm Registry are:
0: No BIER specific algorithm is used
1-254: Unassigned
255: Reserved
4. Concepts 4. Concepts
4.1. BIER Domains and Sub-Domains 4.1. BIER Domains and Sub-Domains
An ISIS signalled BIER domain is aligned with the scope of An ISIS signalled BIER domain is aligned with the scope of
distribution of BFR-prefixes that identify the BFRs within ISIS. distribution of BFR-prefixes that identify the BFRs within ISIS.
ISIS acts in such a case as the supporting BIER underlay. ISIS acts in such a case as the supporting BIER underlay.
Within such a domain, the extensions defined in this document Within such a domain, the extensions defined in this document
advertise BIER information for one or more BIER sub-domains. Each advertise BIER information for one or more BIER sub-domains. Each
sub-domain is uniquely identified by a subdomain-id. Each subdomain sub-domain is uniquely identified by a subdomain-id (SD). Each
is associated with a single ISIS topology [RFC5120], which may be any subdomain is associated with a single ISIS topology (MT) [RFC5120],
of the topologies supported by ISIS. Local configuration controls which may be any of the topologies supported by ISIS. Local
which <MT,SD> pairs are supported by a router. The mapping of sub- configuration controls which <MT,SD> pairs are supported by a router.
domains to topologies MUST be consistent within the IS-IS flooding The mapping of sub-domains to topologies MUST be consistent within
domain used to advertise BIER information. the IS-IS flooding domain used to advertise BIER information.
Each BIER sub-domain has as its unique attributes the encapsulation Each BIER sub-domain has as its unique attributes the encapsulation
used and the type of tree it is using to forward BIER frames used and the type of tree it is using to forward BIER frames
(currently always SPF). Additionally, per supported bitstring length (currently always SPF). Additionally, per supported bitstring length
in the sub-domain, each router will advertise the necessary label in the sub-domain, each router will advertise the necessary label
ranges to support it. ranges to support it.
4.2. Advertising BIER Information 4.2. Advertising BIER Information
BIER information advertisements are associated with a new sub-TLV in BIER information advertisements are associated with a new sub-TLV in
skipping to change at page 5, line 32 skipping to change at page 6, line 16
Example: Example:
The following combination of advertisements are valid: <0,0> <0,1> The following combination of advertisements are valid: <0,0> <0,1>
<2,2>. <2,2>.
The following combination of advertisements are invalid: <0,0> <0,1> The following combination of advertisements are invalid: <0,0> <0,1>
<2,0>. Advertisements associated with <0,0> and <2,0> MUST be <2,0>. Advertisements associated with <0,0> and <2,0> MUST be
ignored. ignored.
5.2. Encapsulation 5.2. Label advertisements for MPLS Encapsulation
Multiple encapsulations MAY be advertised/supported for a given
<MT,SD>. Clearly, however, there MUST be at least one encapsulation
type in common in order for a BIER encapsulated packet to be
successfully forwarded between two BFRs.
5.3. BIER Algorithm
All routers in the flooding scope of the BIER TLVs MUST advertise a
supported algorithm for a given <MT,SD>. The specified algorithm is
used when calculating the optimal path. The supported algorithm MUST
be consistent for all routers supporting a given <MT,SD>. A router
receiving an <MT,SD> advertisement with a BAR which does not match
the locally configured value MUST report a misconfiguration of the
received <MT, SD> pair. All received BIER advertisements associated
with the conflicting <MT, SD> pair MUST be ignored.
Currently only the default algorithm "SPF" is defined - which has a
reserved value of 0 and represents Shortest Path First (SPF) based on
IGP link metric. This is the standard shortest path algorithm as
computed by the IS-IS protocol.
5.4. Label advertisements for MPLS Encapsulation
A router that desires to participate in <MT,SD> MUST advertise for A router that desires to participate in <MT,SD> MUST advertise for
each bitstring length it supports in <MT,SD> a Maximum Set ID that each bitstring length it supports in <MT,SD> a Maximum Set ID that
guarantees to cover the maximum BFR-id injected into <MT,SD> (which guarantees to cover the maximum BFR-id injected into <MT,SD> (which
implies a certain maximum set id per bitstring length as described in implies a certain maximum set id per bitstring length as described in
[RFC8279]). Any router that violates this condition MUST be excluded [RFC8279]). Any router that violates this condition MUST be excluded
from BIER BFTs for <MT,SD>. from BIER BFTs for <MT,SD>.
5.5. BFR-id Advertisements 5.3. BFR-id Advertisements
Each BFER/BFIR MAY advertise with its TLV<MT,SD> the BFR-id that it Each BFER/BFIR MAY advertise with its TLV<MT,SD> the BFR-id that it
has administratively chosen. A valid BFR-id MUST be unique within has administratively chosen. A valid BFR-id MUST be unique within
the flooding scope of the BIER advertisements. All BFERs/BFIRs MUST the flooding scope of the BIER advertisements. All BFERs/BFIRs MUST
detect advertisement of duplicate valid BFR-IDs for a given <MT, SD>. detect advertisement of duplicate valid BFR-IDs for a given <MT, SD>.
When such duplication is detected all of the routers advertising When such duplication is detected all of the routers advertising
duplicates MUST be treated as if they did not advertise a valid BFR- duplicates MUST be treated as if they did not advertise a valid BFR-
id. This implies they cannot act as BFER or BFIR in that <MT,SD>. id. This implies they cannot act as BFER or BFIR in that <MT,SD>.
5.6. Reporting Misconfiguration 5.4. Logging Misconfiguration
Whenever an advertisement is received which violates any of the Whenever an advertisement is received which violates any of the
constraints defined in this document the receiving router MUST report constraints defined in this document the receiving router MUST
the misconfiguration. Such reports SHOULD be dampened to avoid support logging this occurrence. Logging SHOULD be dampened to avoid
excessive logging output. excessive output.
5.7. Flooding Reduction 5.5. Flooding Reduction
BIER domain information SHOULD change infrequently. Frequent changes BIER domain information SHOULD change infrequently. Frequent changes
will increase the number of Link State PDU (LSP) updates and will increase the number of Link State PDU (LSP) updates and
negatively impact performance in the network. negatively impact performance in the network.
6. Packet Formats 6. Packet Formats
All ISIS BIER information is carried within the TLVs 235, 237 All ISIS BIER information is carried within the TLVs 235, 237
[RFC5120] or TLVs 135 [RFC5305], or TLV 236 [RFC5308]. [RFC5120] or TLVs 135 [RFC5305], or TLV 236 [RFC5308].
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times in a given prefix-reachability TLV - once for each sub-domain times in a given prefix-reachability TLV - once for each sub-domain
supported in the associated topology. supported in the associated topology.
The sub-TLV advertises a single <MT,SD> combination followed by The sub-TLV advertises a single <MT,SD> combination followed by
optional sub-sub-TLVs as described in the following sections. optional sub-sub-TLVs as described in the following sections.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BAR | subdomain-id | BFR-id | | BAR | IPA | subdomain-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFR-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-sub-TLVs (variable) | | sub-sub-TLVs (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: as indicated in IANA section. Type: as indicated in IANA section.
Length: variable Length: variable
BAR BIER Algorithm. 0 is the only supported value defined in this BAR BIER Algorithm. Specifies a BIER specific algorithm used to
document. Other values may be defined in the future. 8 bits calculate underlay paths to reach BFERs. Values are allocated
from the BIER Algorithm Registry. 1 octet
IPA IGP algorithm. Specifies an IGP Algorithm to either modify,
enhance or replace the calculation of underlay paths to reach
BFERs as defined by the BAR value. Values are from the IGP
Algorithm registry. 1 octet
subdomain-id: Unique value identifying the BIER sub-domain. 1 octet subdomain-id: Unique value identifying the BIER sub-domain. 1 octet
BFR-id: A 2 octet field encoding the BFR-id, as documented in BFR-id: A 2 octet field encoding the BFR-id, as documented in
[RFC8279]. If no BFR-id has been assigned this field is set to [RFC8279]. If no BFR-id has been assigned this field is set to
the invalid BFR-id. the invalid BFR-id.
The use of non-zero values in either the BAR field or the IPA field
is outside the scope of this document. If an implementation does not
support the use of non-zero values in these fields, but receives a
BIER Info sub-TLV containing non-zero values in these fields, it
SHOULD treat the advertising router as incapable of supporting BIER
(one way of handling incapable routers is documented in section 6.9
of [RFC8279] and additional methods may be defined in the future).
6.2. BIER MPLS Encapsulation sub-sub-TLV 6.2. BIER MPLS Encapsulation sub-sub-TLV
This sub-sub-TLV carries the information for the BIER MPLS This sub-sub-TLV carries the information for the BIER MPLS
encapsulation including the label range for a specific bitstring encapsulation including the label range for a specific bitstring
length for a certain <MT,SD>. It is advertised within the BIER Info length for a certain <MT,SD>. It is advertised within the BIER Info
sub-TLV (Section 6.1) . This sub-sub-TLV MAY appear multiple times sub-TLV (Section 6.1) . This sub-sub-TLV MAY appear multiple times
within a single BIER info sub-TLV. within a single BIER info sub-TLV.
On violation of any of the following conditions, the receiving router On violation of any of the following conditions, the receiving router
MUST ignore the encapsulating BIER Info sub-TLV. MUST ignore the encapsulating BIER Info sub-TLV.
o Label ranges in multiple sub-sub-TLV MUST NOT overlap. o Label ranges in multiple sub-sub-TLVs MUST NOT overlap.
o Bitstring lengths in multiple sub-sub-TLVs MUST NOT be identical. o Bitstring lengths in multiple sub-sub-TLVs MUST NOT be identical.
o The sub-sub-TLV MUST include the required bitstring lengths o The sub-sub-TLV MUST include the required bitstring lengths
encoded in precisely the same way as in [RFC8296]. encoded in precisely the same way as in [RFC8296].
o All labels in the range MUST represent valid label values o All labels in the range MUST represent valid label values
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max SI |BS Len | Label | | Max SI |BS Len | Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: value of 1 indicating MPLS encapsulation. Type: value of 1 indicating MPLS encapsulation.
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Max SI Maximum Set Identifier (section 1 of [RFC8279]) used in the Max SI Maximum Set Identifier (section 1 of [RFC8279]) used in the
encapsulation for this BIER sub-domain for this bitstring length, encapsulation for this BIER sub-domain for this bitstring length,
1 octet. Each SI maps to a single label in the label range. The 1 octet. Each SI maps to a single label in the label range. The
first label is for SI=0, the second label is for SI=1, etc. first label is for SI=0, the second label is for SI=1, etc.
Label: First label of the range, 20 bits. The labels are as defined Label: First label of the range, 20 bits. The labels are as defined
in [RFC8296]. in [RFC8296].
7. Security Considerations 7. Security Considerations
Implementations must assure that malformed TLV and Sub-TLV Security concerns for IS-IS are addressed in [RFC5304] and [RFC5310].
permutations do not result in errors which cause hard protocol Advertisement of the additional information defined in this document
failures. introduces no new security concerns.
BIER specific security considerations are discussed in [RFC8279].
8. Acknowledgements 8. Acknowledgements
The RFC is aligned with the The RFC is aligned with the
[I-D.draft-ietf-bier-ospf-bier-extensions-10] draft as far as the [I-D.draft-ietf-bier-ospf-bier-extensions-14] draft as far as the
protocol mechanisms overlap. protocol mechanisms overlap.
Many thanks for comments from (in no particular order) Hannes Many thanks for comments from (in no particular order) Hannes
Gredler, Ijsbrand Wijnands, Peter Psenak and Chris Bowers. Gredler, Ijsbrand Wijnands, Peter Psenak and Chris Bowers.
9. References 9. References
9.1. Normative References 9.1. Normative References
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and [RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
skipping to change at page 9, line 16 skipping to change at page 9, line 46
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi [RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120, Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008, DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>. <https://www.rfc-editor.org/info/rfc5120>.
[RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic
Authentication", RFC 5304, DOI 10.17487/RFC5304, October
2008, <https://www.rfc-editor.org/info/rfc5304>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>. 2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308, [RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308,
DOI 10.17487/RFC5308, October 2008, DOI 10.17487/RFC5308, October 2008,
<https://www.rfc-editor.org/info/rfc5308>. <https://www.rfc-editor.org/info/rfc5308>.
[RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R.,
and M. Fanto, "IS-IS Generic Cryptographic
Authentication", RFC 5310, DOI 10.17487/RFC5310, February
2009, <https://www.rfc-editor.org/info/rfc5310>.
[RFC7794] Ginsberg, L., Ed., Decraene, B., Previdi, S., Xu, X., and [RFC7794] Ginsberg, L., Ed., Decraene, B., Previdi, S., Xu, X., and
U. Chunduri, "IS-IS Prefix Attributes for Extended IPv4 U. Chunduri, "IS-IS Prefix Attributes for Extended IPv4
and IPv6 Reachability", RFC 7794, DOI 10.17487/RFC7794, and IPv6 Reachability", RFC 7794, DOI 10.17487/RFC7794,
March 2016, <https://www.rfc-editor.org/info/rfc7794>. March 2016, <https://www.rfc-editor.org/info/rfc7794>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
9.2. Informative References
[I-D.draft-ietf-bier-ospf-bier-extensions-14]
Psenak et al., P., "OSPF Extension for Bit Index Explicit
Replication", internet-draft draft-ietf-bier-ospf-bier-
extensions-14, February 2018.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., [RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Przygienda, T., and S. Aldrin, "Multicast Using Bit Index Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
Explicit Replication (BIER)", RFC 8279, Explicit Replication (BIER)", RFC 8279,
DOI 10.17487/RFC8279, November 2017, DOI 10.17487/RFC8279, November 2017,
<https://www.rfc-editor.org/info/rfc8279>. <https://www.rfc-editor.org/info/rfc8279>.
[RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., [RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation
for Bit Index Explicit Replication (BIER) in MPLS and Non- for Bit Index Explicit Replication (BIER) in MPLS and Non-
MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January
2018, <https://www.rfc-editor.org/info/rfc8296>. 2018, <https://www.rfc-editor.org/info/rfc8296>.
9.2. Informative References
[I-D.draft-ietf-bier-ospf-bier-extensions-10]
Psenak et al., P., "OSPF Extension for Bit Index Explicit
Replication", internet-draft draft-ietf-bier-ospf-bier-
extensions-09.txt, Dec 2017.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
Authors' Addresses Authors' Addresses
Les Ginsberg (editor) Les Ginsberg (editor)
Cisco Systems Cisco Systems
510 McCarthy Blvd. 510 McCarthy Blvd.
Milpitas, CA 95035 Milpitas, CA 95035
USA USA
Email: ginsberg@cisco.com Email: ginsberg@cisco.com
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