< draft-ietf-6man-ipv6-alt-mark-02.txt   draft-ietf-6man-ipv6-alt-mark-03.txt >
6MAN Working Group G. Fioccola 6MAN Working Group G. Fioccola
Internet-Draft T. Zhou Internet-Draft T. Zhou
Intended status: Standards Track Huawei Intended status: Standards Track Huawei
Expires: April 16, 2021 M. Cociglio Expires: August 1, 2021 M. Cociglio
Telecom Italia Telecom Italia
F. Qin F. Qin
China Mobile China Mobile
R. Pang R. Pang
China Unicom China Unicom
October 13, 2020 January 28, 2021
IPv6 Application of the Alternate Marking Method IPv6 Application of the Alternate Marking Method
draft-ietf-6man-ipv6-alt-mark-02 draft-ietf-6man-ipv6-alt-mark-03
Abstract Abstract
This document describes how the Alternate Marking Method can be used This document describes how the Alternate Marking Method can be used
as the passive performance measurement tool in an IPv6 domain and as the passive performance measurement tool in an IPv6 domain and
reports implementation considerations. It proposes how to define a reports implementation considerations. It proposes how to define a
new Extension Header Option to encode alternate marking technique and new Extension Header Option to encode alternate marking technique and
both Hop-by-Hop Options Header and Destination Options Header are both Hop-by-Hop Options Header and Destination Options Header are
considered. considered.
skipping to change at page 1, line 49 skipping to change at page 1, line 49
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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 April 16, 2021. This Internet-Draft will expire on August 1, 2021.
Copyright Notice Copyright Notice
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document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Alternate Marking application to IPv6 . . . . . . . . . . . . 3 2. Alternate Marking application to IPv6 . . . . . . . . . . . . 3
3. Definition of the AltMark Option . . . . . . . . . . . . . . 4 2.1. Controlled Domain . . . . . . . . . . . . . . . . . . . . 4
3.1. Data Fields Format . . . . . . . . . . . . . . . . . . . 4 3. Definition of the AltMark Option . . . . . . . . . . . . . . 5
4. Use of the AltMark Option . . . . . . . . . . . . . . . . . . 5 3.1. Data Fields Format . . . . . . . . . . . . . . . . . . . 5
5. Alternate Marking Method Operation . . . . . . . . . . . . . 7 4. Use of the AltMark Option . . . . . . . . . . . . . . . . . . 6
5.1. Packet Loss Measurement . . . . . . . . . . . . . . . . . 7 5. Alternate Marking Method Operation . . . . . . . . . . . . . 8
5.2. Packet Delay Measurement . . . . . . . . . . . . . . . . 8 5.1. Packet Loss Measurement . . . . . . . . . . . . . . . . . 8
5.2. Packet Delay Measurement . . . . . . . . . . . . . . . . 9
5.3. Flow Monitoring Identification . . . . . . . . . . . . . 10 5.3. Flow Monitoring Identification . . . . . . . . . . . . . 10
5.3.1. Uniqueness of FlowMonID . . . . . . . . . . . . . . . 10 5.3.1. Uniqueness of FlowMonID . . . . . . . . . . . . . . . 11
5.4. Multipoint and Clustered Alternate Marking . . . . . . . 11 5.4. Multipoint and Clustered Alternate Marking . . . . . . . 12
5.5. Data Collection and Calculation . . . . . . . . . . . . . 11 5.5. Data Collection and Calculation . . . . . . . . . . . . . 12
6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . 13 9.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . 13 9.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
[RFC8321] and [RFC8889] describe a passive performance measurement [RFC8321] and [RFC8889] describe a passive performance measurement
method, which can be used to measure packet loss, latency and jitter method, which can be used to measure packet loss, latency and jitter
on live traffic. Since this method is based on marking consecutive on live traffic. Since this method is based on marking consecutive
batches of packets, the method is often referred as Alternate Marking batches of packets, the method is often referred as Alternate Marking
Method. Method.
The Alternate Marking Method has become mature to be implemented and The Alternate Marking Method has became mature to be implemented and
encoded in the IPv6 protocol and this document defines how it can be encoded in the IPv6 protocol and this document defines how it can be
used to measure packet loss and delay metrics in IPv6. used to measure packet loss and delay metrics in IPv6.
The format of the IPv6 addresses is defined in [RFC4291] while The format of the IPv6 addresses is defined in [RFC4291] while
[RFC8200] defines the IPv6 Header, including a 20-bit Flow Label and [RFC8200] defines the IPv6 Header, including a 20-bit Flow Label and
the IPv6 Extension Headers. The Segment Routing Header (SRH) is the IPv6 Extension Headers. The Segment Routing Header (SRH) is
defined in [RFC8754] to apply Segment Routing over IPv6 dataplane defined in [RFC8754] to apply Segment Routing over IPv6 dataplane
(SRv6). (SRv6).
[I-D.fioccola-v6ops-ipv6-alt-mark] reported a summary on the possible [I-D.fioccola-v6ops-ipv6-alt-mark] summarizes the possible
implementation options for the application of the Alternate Marking implementation options for the application of the Alternate Marking
Method in an IPv6 domain. This document, starting from the outcome Method in an IPv6 domain. This document, starting from the outcome
of [I-D.fioccola-v6ops-ipv6-alt-mark], introduces a new TLV that can of [I-D.fioccola-v6ops-ipv6-alt-mark], introduces a new TLV that can
be encoded in the Options Headers (both Hop-by-Hop or Destination) be encoded in the Options Headers (both Hop-by-Hop or Destination)
for the purpose of the Alternate Marking Method application in an for the purpose of the Alternate Marking Method application in an
IPv6 domain. The case of SRH ([RFC8754]) is also discussed, anyway IPv6 domain. The case of SRH ([RFC8754]) is also discussed, anyway
this is valid for all the types of Routing Header (RH). this is valid for all the types of Routing Header (RH).
2. Alternate Marking application to IPv6 2. Alternate Marking application to IPv6
The Alternate Marking Method requires a marking field. As mentioned, The Alternate Marking Method requires a marking field. As mentioned,
several alternatives have been analysed in several alternatives have been analysed in
[I-D.fioccola-v6ops-ipv6-alt-mark] such as IPv6 Extension Headers, [I-D.fioccola-v6ops-ipv6-alt-mark] such as IPv6 Extension Headers,
IPv6 Address and Flow Label. IPv6 Address and Flow Label.
In consequence to the previous document and to the discussion within Consequently, it is possible to state that the only robust choice is
the community, it is possible to state that the only correct and to standardize a new Hop-by-Hop or Destination Option.
robust choice that can actually be standardized would be the use of a
new TLV to be encoded in the Options Header (Hop-by-Hop or
Destination Option).
This approach is compliant with [RFC8200] indeed the Alternate This approach is compliant with [RFC8200] indeed the Alternate
Marking application to IPv6 involves the following operations: Marking application to IPv6 involves the following operations:
o The source node is the only one that writes the Option Header to o The source node is the only one that writes the Option Header to
mark alternately the flow (for both Hop-by-Hop and Destination mark alternately the flow (for both Hop-by-Hop and Destination
Option). Option).
o In case of Hop-by-Hop Option Header carrying Alternate Marking o In case of Hop-by-Hop Option Header carrying Alternate Marking
bits, it is not inserted or deleted, but can be read by any node bits, it is not inserted or deleted, but can be read by any node
along the path. The intermediate nodes may be configured to along the path. The intermediate nodes may be configured to
support this Option or not. Anyway this does not impact the support this Option or not. Anyway this does not impact the
traffic since the measurement can be done only for the nodes traffic throughput since the measurement can be done only for the
configured to read the Option. nodes configured to read the Option.
o In case of Destination Option Header carrying Alternate Marking o In case of Destination Option Header carrying Alternate Marking
bits, it is not processed, inserted, or deleted by any node along bits, it is not processed, inserted, or deleted by any node along
the path until the packet reaches the destination node. Note the path until the packet reaches the destination node. Note
that, if there is also a Routing Header (RH), any visited that, if there is also a Routing Header (RH), any visited
destination in the route list can process the Option Header. destination in the route list can process the Option Header.
Hop-by-Hop Option Header is also useful to signal to routers on the Hop-by-Hop Option Header is also useful to signal to routers on the
path to process the Alternate Marking, anyway it is to be expected path to process the Alternate Marking, anyway it is to be expected
that some routers cannot process it unless explicitly configured. that some routers cannot process it unless explicitly configured.
The optimization of both implementation and scaling of the Alternate The optimization of both implementation and scaling of the Alternate
Marking Method is also considered and a way to identify flows is Marking Method is also considered and a way to identify flows is
required. The Flow Monitoring Identification field (FlowMonID), as required. The Flow Monitoring Identification field (FlowMonID), as
introduced in the next sections, goes in this direction and it is introduced in the next sections, goes in this direction and it is
used to identify a monitored flow. used to identify a monitored flow.
Note that the FlowMonID is different from the Flow Label field of the Note that the FlowMonID is different from the Flow Label field of the
IPv6 Header ([RFC8200]). Flow Label is used for application service, IPv6 Header ([RFC8200]). Flow Label is used for load-balancing/equal
like load-balancing/equal cost multi-path (LB/ECMP) and QoS. cost multi-path (LB/ECMP). Instead, FlowMonID is only used to
Instead, FlowMonID is only used to identify the monitored flow. The identify the monitored flow. The reuse of flow label field for
reuse of flow label field for identifying monitored flows is not identifying monitored flows is not considered since it may change the
considered since it may change the application intent and forwarding application intent and forwarding behaviour. Furthermore the flow
behaviour. Furthermore the flow label may be changed en route and label may be changed en route and this may also violate the
this may also violate the measurement task. Those reasons make the measurement task. Also, since the flow label is pseudo-random, there
is always a finite probability of collision. Those reasons make the
definition of the FlowMonID necessary for IPv6. Flow Label and definition of the FlowMonID necessary for IPv6. Flow Label and
FlowMonID within the same packet have different scope, identify FlowMonID within the same packet have different scope, identify
different flows, and associate different uses. different flows, and associate different uses.
An important point that will also be discussed in this document is An important point that will also be discussed in this document is
the the uniqueness of the FlowMonID and how to allow disambiguation the the uniqueness of the FlowMonID and how to allow disambiguation
of the FlowMonID in case of collision. [RFC6437] states that the of the FlowMonID in case of collision. [RFC6437] states that the
Flow Label cannot be considered alone to avoid ambiguity since it Flow Label cannot be considered alone to avoid ambiguity since it
could be accidentally or intentionally changed en route for could be accidentally or intentionally changed en route for
compelling operational security reasons and this could also happen to compelling operational security reasons and this could also happen to
the IP addresses that can change due to NAT. But the Alternate the IP addresses that can change due to NAT. But the Alternate
Marking is usually applied in a controlled domain, which would not Marking is usually applied in a controlled domain, which would not
have NAT and there is no security issue that would necessitate have NAT and there is no security issue that would necessitate
rewriting Flow Labels. So, for the purposes of this document, both rewriting Flow Labels. So, for the purposes of this document, both
IP addresses and Flow Label should not change in flight and, in some IP addresses and Flow Label should not change in flight and, in some
cases, they could be considered together with the FlowMonID for cases, they could be considered together with the FlowMonID for
disambiguation. disambiguation.
2.1. Controlled Domain
[RFC8799] introduces the concept of specific limited domain solutions
and, in this regard, it is reported the IPv6 Application of the
Alternate Marking Method as an example.
IPv6 has much more flexibility than IPv4 and innovative applications
have been proposed, but for a number of reasons, such as the options
supported, the style of network management and security requirements,
it is suggested to limit some of these applications to a controlled
domain. This is also the case of the Alternate Marking application
to IPv6 as assumed hereinafter.
3. Definition of the AltMark Option 3. Definition of the AltMark Option
The desired choice is to define a new TLV for the Options Extension The desired choice is to define a new TLV for the Options Extension
Headers, carrying the data fields dedicated to the alternate marking Headers, carrying the data fields dedicated to the alternate marking
method. method.
3.1. Data Fields Format 3.1. Data Fields Format
The following figure shows the data fields format for enhanced The following figure shows the data fields format for enhanced
alternate marking TLV. This AltMark data is expected to be alternate marking TLV. This AltMark data is expected to be
skipping to change at page 5, line 50 skipping to change at page 6, line 17
4. Use of the AltMark Option 4. Use of the AltMark Option
The AltMark Option is the best way to implement the Alternate Marking The AltMark Option is the best way to implement the Alternate Marking
method and can be carried by the Hop-by-Hop Options header and the method and can be carried by the Hop-by-Hop Options header and the
Destination Options header. In case of Destination Option, it is Destination Options header. In case of Destination Option, it is
processed only by the source and destination nodes: the source node processed only by the source and destination nodes: the source node
inserts and the destination node removes it. While, in case of Hop- inserts and the destination node removes it. While, in case of Hop-
by-Hop Option, it may be examined by any node along the path, if by-Hop Option, it may be examined by any node along the path, if
explicitly configured to do so. In this way an unrecognized Hop-by- explicitly configured to do so. In this way an unrecognized Hop-by-
Hop Option may be just ignored without impacting the traffic. Hop Option may be just ignored without any impact.
So it is important to highlight that the Option Layout can be used So it is important to highlight that the Option Layout can be used
both as Destination Option and as Hop-by-Hop Option depending on the both as Destination Option and as Hop-by-Hop Option depending on the
Use Cases and it is based on the chosen type of performance Use Cases and it is based on the chosen type of performance
measurement. In general, it is needed to perform both end to end and measurement. In general, it is needed to perform both end to end and
hop by hop measurements, and the alternate marking methodology hop by hop measurements, and the alternate marking methodology
allows, by definition, both performance measurements. Anyway, in allows, by definition, both performance measurements. Anyway, in
many cases the end-to-end measurement is not enough and it is many cases the end-to-end measurement is not enough and it is
required also the hop-by-hop measurement, so the most complete choice required also the hop-by-hop measurement, so the most complete choice
is the Hop-by-Hop Options Header. is the Hop-by-Hop Options Header.
skipping to change at page 6, line 42 skipping to change at page 7, line 7
leverages the Segment Routing header which consists of a new type of leverages the Segment Routing header which consists of a new type of
routing header. Like any other use case of IPv6, Hop-by-Hop and routing header. Like any other use case of IPv6, Hop-by-Hop and
Destination Options are useable when SRv6 header is present. Because Destination Options are useable when SRv6 header is present. Because
SRv6 is implemented through a Segment Routing Header (SRH), SRv6 is implemented through a Segment Routing Header (SRH),
Destination Options before the Routing Header are processed by each Destination Options before the Routing Header are processed by each
destination in the route list, that means, in case of SRH, by every destination in the route list, that means, in case of SRH, by every
node that is an identity in the SR path. node that is an identity in the SR path.
In summary, it is possible to list the alternative possibilities: In summary, it is possible to list the alternative possibilities:
o Destination Option => measurement only by node in Destination o Destination Option not preceding a Routing Header => measurement
Address. only by node in Destination Address.
o Hop-by-Hop Option => every router on the path with feature o Hop-by-Hop Option => every router on the path with feature
enabled. enabled.
o Destination Option + any Routing Header => every destination node o Destination Option preceding a Routing Header => every destination
in the route list. node in the route list.
In general, Hop-by-Hop and Destination Options are the most suitable In general, Hop-by-Hop and Destination Options are the most suitable
ways to implement Alternate Marking. ways to implement Alternate Marking.
It is worth mentioning that new Hop-by-Hop Options are not strongly It is worth mentioning that new Hop-by-Hop Options are not strongly
recommended in [RFC7045] and [RFC8200], unless there is a clear recommended in [RFC7045] and [RFC8200], unless there is a clear
justification to standardize it, because nodes may be configured to justification to standardize it, because nodes may be configured to
ignore the Options Header, drop or assign packets containing an ignore the Options Header, drop or assign packets containing an
Options Header to a slow processing path. In case of the AltMark Options Header to a slow processing path. In case of the AltMark
data fields described in this document, the motivation to standardize data fields described in this document, the motivation to standardize
a new Hop-by-Hop Option is that it is needed for OAM. An a new Hop-by-Hop Option is that it is needed for OAM. An
intermediate node can read it or not but this does not affect the intermediate node can read it or not but this does not affect the
packet behavior. The source node is the only one that writes the packet behavior. The source node is the only one that writes the
Hop-by-Hop Option to mark alternately the flow, so, the performance Hop-by-Hop Option to mark alternately the flow, so, the performance
measurement can be done for those nodes configured to read this measurement can be done for those nodes configured to read this
Option, while the others are simply not considered for the metrics. Option, while the others are simply not considered for the metrics.
It is important to highlight that the definition of the Hop-by-Hop
Options in this document SHOULD not affect the throughput on nodes
that do not recognize the Option. Indeed, the three high-order bits
of the Options Header defined in this draft are 000 and, in theory,
as per [RFC8200] and [I-D.hinden-6man-hbh-processing], this means
"skip if do not recognize and data do not change en route".
[RFC8200] also mentions that the nodes only examine and process the
Hop-by-Hop Options header if explicitly configured to do so. For
these reasons, this HbH Option should not affect the throughput.
Anyway, in practice, it is important to be aware for the
implementation that the things may be different and it can happen
that packets with Hop-by-Hop are forced onto the slow path, but this
is a general issue, as also explained in
[I-D.hinden-6man-hbh-processing].
In addition to the previous alternatives, for legacy network it is In addition to the previous alternatives, for legacy network it is
possible to mention a non-conventional application of the Destination possible to mention a non-conventional application of the Destination
Option for the hop by hop usage. [RFC8200] defines that the nodes Option for the hop by hop usage. [RFC8200] defines that the nodes
along a path examine and process the Hop-by-Hop Options header only along a path examine and process the Hop-by-Hop Options header only
if Hop-by-Hop processing is explicitly configured. On the other if Hop-by-Hop processing is explicitly configured. On the other
hand, using the Destination Option for hop by hop action would cause hand, using the Destination Option for hop by hop action would cause
worse performance than Hop-by-Hop. The only motivation for the hop worse performance than Hop-by-Hop. The only motivation for the hop
by hop usage of Destination Options can be for compatibility reasons by hop usage of Destination Options can be for compatibility reasons
but in general it is not recommended. but in general it is not recommended.
5. Alternate Marking Method Operation 5. Alternate Marking Method Operation
This section describes how the method operates. [RFC8321] introduces This section describes how the method operates. [RFC8321] introduces
several alternatives but in this section the most applicable methods several alternatives but in this section the most applicable methods
are reported and a new fied is introduced to facilitate the are reported and a new field is introduced to facilitate the
deployment and improve the scalability. deployment and improve the scalability.
5.1. Packet Loss Measurement 5.1. Packet Loss Measurement
The measurement of the packet loss is really straightforward. The The measurement of the packet loss is really straightforward. The
packets of the flow are grouped into batches, and all the packets packets of the flow are grouped into batches, and all the packets
within a batch are marked by setting the L bit (Loss flag) to a same within a batch are marked by setting the L bit (Loss flag) to a same
value. The source node can switch the value of the L bit between 0 value. The source node can switch the value of the L bit between 0
and 1 after a fixed number of packets or according to a fixed timer, and 1 after a fixed number of packets or according to a fixed timer,
and this depends on the implementation. By counting the number of and this depends on the implementation. By counting the number of
skipping to change at page 11, line 5 skipping to change at page 11, line 40
it is possible to consider the hashed 3-tuple Flow Label, Source and it is possible to consider the hashed 3-tuple Flow Label, Source and
Destination addresses) or the FlowMonID size could be increased. Destination addresses) or the FlowMonID size could be increased.
This issue is more visible when the FlowMonID is pseudo randomly This issue is more visible when the FlowMonID is pseudo randomly
generated by the source node and there needs to tag it with generated by the source node and there needs to tag it with
additional flow information to allow disambiguation. While, in case additional flow information to allow disambiguation. While, in case
of a centralized controller, the controller should set FlowMonID by of a centralized controller, the controller should set FlowMonID by
considering these aspects and instruct the nodes properly in order to considering these aspects and instruct the nodes properly in order to
guarantee its uniqueness. guarantee its uniqueness.
Anyway, it is worth highlighting that the uniqueness of FlowMonID may
not be a problem and a low rate of ambiguous FlowMonIDs can be
acceptable, since this does not cause significant harm to the
operators or their clients and this harm may not justify the
complications of avoiding it. But, for large scale measurements
where it is possible to monitor a big number of flows, the
disambiguation of the Flow Monitoring Identification field is
something to take into account.
5.4. Multipoint and Clustered Alternate Marking 5.4. Multipoint and Clustered Alternate Marking
The Alternate Marking method can also be extended to any kind of The Alternate Marking method can also be extended to any kind of
multipoint to multipoint paths, and the network clustering approach multipoint to multipoint paths, and the network clustering approach
allows a flexible and optimized performance measurement, as described allows a flexible and optimized performance measurement, as described
in [RFC8889]. in [RFC8889].
The Cluster is the smallest identifiable subnetwork of the entire The Cluster is the smallest identifiable subnetwork of the entire
Network graph that still satisfies the condition that the number of Network graph that still satisfies the condition that the number of
packets that goes in is the same that goes out. With network packets that goes in is the same that goes out. With network
skipping to change at page 12, line 18 skipping to change at page 13, line 18
where the network nodes are locally administered and this type of where the network nodes are locally administered and this type of
attack can be avoided. Indeed the source and destination addresses attack can be avoided. Indeed the source and destination addresses
are within the controlled domain and therefore it is unlikely subject are within the controlled domain and therefore it is unlikely subject
to hijacking of packets, because it is possible to filter external to hijacking of packets, because it is possible to filter external
packets at the domain boundaries. In addition, an attacker cannot packets at the domain boundaries. In addition, an attacker cannot
gain information about network performance from a single monitoring gain information about network performance from a single monitoring
point; it must use synchronized monitoring points at multiple points point; it must use synchronized monitoring points at multiple points
on the path, because they have to do the same kind of measurement and on the path, because they have to do the same kind of measurement and
aggregation as Alternate Marking requires. aggregation as Alternate Marking requires.
Additionally, it is to be noted that Alternate Marking bits are
carried by the Options Header and it may have some impact on the
packet sizes for the monitored flow and on the path MTU, since some
packets might exceed the MTU. Anyway the relative small size (48 bit
in total) of these Option Headers and its application to a controlled
domain help to mitigate the problem.
The privacy concerns of network measurement are limited because the The privacy concerns of network measurement are limited because the
method only relies on information contained in the Option Header method only relies on information contained in the Option Header
without any release of user data. Although information in the Option without any release of user data. Although information in the Option
Header is metadata that can be used to compromise the privacy of Header is metadata that can be used to compromise the privacy of
users, the limited marking technique seems unlikely to substantially users, the limited marking technique seems unlikely to substantially
increase the existing privacy risks from header or encapsulation increase the existing privacy risks from header or encapsulation
metadata. metadata.
The Alternate Marking application described in this document relies The Alternate Marking application described in this document relies
on an time synchronization protocol. Thus, by attacking the time on an time synchronization protocol. Thus, by attacking the time
skipping to change at page 13, line 8 skipping to change at page 14, line 13
(https://www.iana.org/assignments/ipv6-parameters/). (https://www.iana.org/assignments/ipv6-parameters/).
Hex Value Binary Value Description Reference Hex Value Binary Value Description Reference
act chg rest act chg rest
---------------------------------------------------------------- ----------------------------------------------------------------
TBD 00 0 tbd AltMark [This draft] TBD 00 0 tbd AltMark [This draft]
8. Acknowledgements 8. Acknowledgements
The authors would like to thank Bob Hinden, Ole Troan, Tom Herbert, The authors would like to thank Bob Hinden, Ole Troan, Tom Herbert,
Stefano Previdi, Brian Carpenter, Eric Vyncke, Ron Bonica for the Stefano Previdi, Brian Carpenter, Eric Vyncke, Ron Bonica, Greg
precious comments and suggestions. Mirsky for the precious comments and suggestions.
9. References 9. References
9.1. Normative References 9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
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>.
skipping to change at page 13, line 37 skipping to change at page 14, line 42
<https://www.rfc-editor.org/info/rfc8200>. <https://www.rfc-editor.org/info/rfc8200>.
9.2. Informative References 9.2. Informative References
[I-D.fioccola-v6ops-ipv6-alt-mark] [I-D.fioccola-v6ops-ipv6-alt-mark]
Fioccola, G., Velde, G., Cociglio, M., and P. Muley, "IPv6 Fioccola, G., Velde, G., Cociglio, M., and P. Muley, "IPv6
Performance Measurement with Alternate Marking Method", Performance Measurement with Alternate Marking Method",
draft-fioccola-v6ops-ipv6-alt-mark-01 (work in progress), draft-fioccola-v6ops-ipv6-alt-mark-01 (work in progress),
June 2018. June 2018.
[I-D.hinden-6man-hbh-processing]
Hinden, R. and G. Fairhurst, "IPv6 Hop-by-Hop Options
Processing Procedures", draft-hinden-6man-hbh-
processing-00 (work in progress), December 2020.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, DOI 10.17487/RFC4291, February Architecture", RFC 4291, DOI 10.17487/RFC4291, February
2006, <https://www.rfc-editor.org/info/rfc4291>. 2006, <https://www.rfc-editor.org/info/rfc4291>.
[RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, [RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", RFC 6437, "IPv6 Flow Label Specification", RFC 6437,
DOI 10.17487/RFC6437, November 2011, DOI 10.17487/RFC6437, November 2011,
<https://www.rfc-editor.org/info/rfc6437>. <https://www.rfc-editor.org/info/rfc6437>.
[RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing [RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing
skipping to change at page 14, line 20 skipping to change at page 15, line 30
L., Chen, M., Zheng, L., Mirsky, G., and T. Mizrahi, L., Chen, M., Zheng, L., Mirsky, G., and T. Mizrahi,
"Alternate-Marking Method for Passive and Hybrid "Alternate-Marking Method for Passive and Hybrid
Performance Monitoring", RFC 8321, DOI 10.17487/RFC8321, Performance Monitoring", RFC 8321, DOI 10.17487/RFC8321,
January 2018, <https://www.rfc-editor.org/info/rfc8321>. January 2018, <https://www.rfc-editor.org/info/rfc8321>.
[RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J., [RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020, (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
<https://www.rfc-editor.org/info/rfc8754>. <https://www.rfc-editor.org/info/rfc8754>.
[RFC8799] Carpenter, B. and B. Liu, "Limited Domains and Internet
Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020,
<https://www.rfc-editor.org/info/rfc8799>.
[RFC8889] Fioccola, G., Ed., Cociglio, M., Sapio, A., and R. Sisto, [RFC8889] Fioccola, G., Ed., Cociglio, M., Sapio, A., and R. Sisto,
"Multipoint Alternate-Marking Method for Passive and "Multipoint Alternate-Marking Method for Passive and
Hybrid Performance Monitoring", RFC 8889, Hybrid Performance Monitoring", RFC 8889,
DOI 10.17487/RFC8889, August 2020, DOI 10.17487/RFC8889, August 2020,
<https://www.rfc-editor.org/info/rfc8889>. <https://www.rfc-editor.org/info/rfc8889>.
Authors' Addresses Authors' Addresses
Giuseppe Fioccola Giuseppe Fioccola
Huawei Huawei
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