6MAN Working Group G. Fioccola
Internet-Draft T. Zhou
Intended status: Standards Track Huawei
Expires: September 9, 2021 M. Cociglio
Telecom Italia
F. Qin
China Mobile
R. Pang
China Unicom
March 8, 2021
IPv6 Application of the Alternate Marking Method
draft-ietf-6man-ipv6-alt-mark-04
Abstract
This document describes how the Alternate Marking Method can be used
as a passive performance measurement tool in an IPv6 domain. It
defines a new Extension Header Option to encode alternate marking
information in both the Hop-by-Hop Options Header and Destination
Options Header.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "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
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 9, 2021.
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Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Alternate Marking application to IPv6 . . . . . . . . . . . . 3
2.1. Controlled Domain . . . . . . . . . . . . . . . . . . . . 4
3. Definition of the AltMark Option . . . . . . . . . . . . . . 5
3.1. Data Fields Format . . . . . . . . . . . . . . . . . . . 5
4. Use of the AltMark Option . . . . . . . . . . . . . . . . . . 6
5. Alternate Marking Method Operation . . . . . . . . . . . . . 8
5.1. Packet Loss Measurement . . . . . . . . . . . . . . . . . 8
5.2. Packet Delay Measurement . . . . . . . . . . . . . . . . 9
5.3. Flow Monitoring Identification . . . . . . . . . . . . . 10
5.3.1. Uniqueness of FlowMonID . . . . . . . . . . . . . . . 11
5.4. Multipoint and Clustered Alternate Marking . . . . . . . 12
5.5. Data Collection and Calculation . . . . . . . . . . . . . 12
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
[RFC8321] and [RFC8889] describe a passive performance measurement
method, which can be used to measure packet loss, latency and jitter
on live traffic. Since this method is based on marking consecutive
batches of packets, the method is often referred as the Alternate
Marking Method.
This document defines how the Alternate Marking Method can be used to
measure packet loss and delay metrics in IPv6.
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The format of IPv6 addresses is defined in [RFC4291] while [RFC8200]
defines the IPv6 Header, including a 20-bit Flow Label and the IPv6
Extension Headers.
[I-D.fioccola-v6ops-ipv6-alt-mark] summarizes the possible
implementation options for the application of the Alternate Marking
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
be encoded in the Options Headers (Hop-by-Hop or Destination) for the
purpose of the Alternate Marking Method application in an IPv6
domain. While the case of Segment Routing Header (SRH), defined in
[RFC8754], is also discussed, it is valid for all the types of
Routing Header (RH).
2. Alternate Marking application to IPv6
The Alternate Marking Method requires a marking field. As mentioned,
several alternatives have been analysed in
[I-D.fioccola-v6ops-ipv6-alt-mark] such as IPv6 Extension Headers,
IPv6 Address and Flow Label.
Consequently, a robust choice is to standardize a new Hop-by-Hop or
Destination Option.
This approach is compliant with [RFC8200]. The Alternate Marking
application to IPv6 involves the following operations:
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
Option).
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
along the path. The intermediate nodes may be configured to
support this Option or not and the measurement can be done only
for the nodes configured to read the Option. Anyway this should
not affect the traffic throughput on nodes that do not recognize
the Option, as further discussed in Section 4.
o In case of Destination Option Header carrying Alternate Marking
bits, it is not processed, inserted, or deleted by any node along
the path until the packet reaches the destination node. Note
that, if there is also a Routing Header (RH), any visited
destination in the route list can process the Option Header.
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
that some routers cannot process it unless explicitly configured.
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The optimization of both implementation and scaling of the Alternate
Marking Method is also considered and a way to identify flows is
required. The Flow Monitoring Identification field (FlowMonID), as
introduced in the next sections, goes in this direction and it is
used to identify a monitored flow.
Note that the FlowMonID is different from the Flow Label field of the
IPv6 Header ([RFC8200]). Flow Label is used for load-balancing/equal
cost multi-path (LB/ECMP). Instead, FlowMonID is only used to
identify the monitored flow. The reuse of flow label field for
identifying monitored flows is not considered since it may change the
application intent and forwarding behaviour. Furthermore the flow
label may be changed en route and this may also violate 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
FlowMonID within the same packet have different scope, identify
different flows, and associate different uses.
An important point that will also be discussed in this document is
the the uniqueness of the FlowMonID and how to allow disambiguation
of the FlowMonID in case of collision. [RFC6437] states that the
Flow Label cannot be considered alone to avoid ambiguity since it
could be accidentally or intentionally changed en route for
compelling operational security reasons and this could also happen to
the IP addresses that can change due to NAT. But the Alternate
Marking is usually applied in a controlled domain, which would not
have NAT and there is no security issue that would necessitate
rewriting Flow Labels. So, for the purposes of this document, both
IP addresses and Flow Label should not change in flight and, in some
cases, they could be considered together with the FlowMonID for
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.
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3. Definition of the AltMark Option
The desired choice is to define a new TLV for the Options Extension
Headers, carrying the data fields dedicated to the alternate marking
method.
3.1. Data Fields Format
The following figure shows the data fields format for enhanced
alternate marking TLV. This AltMark data is expected to be
encapsulated in the IPv6 Options Headers (Hop-by-Hop or Destination
Option).
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Opt Data Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FlowMonID |L|D| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
o Option Type: 8 bit identifier of the type of Option that needs to
be allocated. Unrecognised Types MUST be ignored on receipt. For
Hop-by-Hop Options Header or Destination Options Header, [RFC8200]
defines how to encode the three high-order bits of the Option Type
field. The two high-order bits specify the action that must be
taken if the processing IPv6 node does not recognize the Option
Type; for AltMark these two bits MUST be set to 00 (skip over this
Option and continue processing the header). The third-highest-
order bit specifies whether or not the Option Data can change en
route to the packet's final destination; for AltMark the value of
this bit MUST be set to 0 (Option Data does not change en route).
o Opt Data Len: The length of the Option Data Fields of this Option
in bytes.
o FlowMonID: 20 bits unsigned integer. The FlowMon identifier is
described in Section 5.3.
o L: Loss flag for Packet Loss Measurement as described in
Section 5.1;
o D: Delay flag for Single Packet Delay Measurement as described in
Section 5.2;
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o Reserved: is reserved for future use. These bits MUST be set to
zero on transmission and ignored on receipt.
4. Use of the AltMark Option
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
Destination Options header. In case of Destination Option, it is
processed only by the source and destination nodes: the source node
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
explicitly configured to do 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 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 hop by hop
measurements, and the alternate marking methodology allows, by
definition, both performance measurements. Anyway, in 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 is the Hop-by-Hop
Options Header.
IPv6, as specified in [RFC8200], allows nodes to optionally process
Hop-by-Hop headers. Specifically the Hop-by-Hop Options header is
not inserted or deleted, but may be examined or processed by any node
along a packet's delivery path, until the packet reaches the node (or
each of the set of nodes, in the case of multicast) identified in the
Destination Address field of the IPv6 header. Also, it is expected
that nodes along a packet's delivery path only examine and process
the Hop-by-Hop Options header if explicitly configured to do so.
The Hop-by-Hop Option defined in this document is designed to take
advantage of the property of how Hop-by-Hop options are processed.
Nodes that do not support this Option SHOULD ignore them. This can
mean that, in this case, the performance measurement does not account
for all links and nodes along a path.
Another application that can be mentioned is the presence of a
Routing Header, in particular it is possible to consider SRv6. A new
type of Routing Header, referred as SRH, has been defined for SRv6.
Like any other use case of IPv6, Hop-by-Hop and Destination Options
are useable when SRv6 header is present. Because SRv6 is implemented
through a Segment Routing Header (SRH), Destination Options before
the Routing Header are processed by each destination in the route
list, that means, in case of SRH, by every node that is an identity
in the SR path.
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In summary, it is possible to list the alternative possibilities:
o Destination Option not preceding a Routing Header => measurement
only by node in Destination Address.
o Hop-by-Hop Option => every router on the path with feature
enabled.
o Destination Option preceding a Routing Header => every destination
node in the route list.
In general, Hop-by-Hop and Destination Options are the most suitable
ways to implement Alternate Marking.
It is worth mentioning that new Hop-by-Hop Options are not strongly
recommended in [RFC7045] and [RFC8200], unless there is a clear
justification to standardize it, because nodes may be configured to
ignore the Options Header, drop or assign packets containing an
Options Header to a slow processing path. In case of the AltMark
data fields described in this document, the motivation to standardize
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
packet behavior. The source node is the only one that writes the
Hop-by-Hop Option to mark alternately the flow, so, the performance
measurement can be done for those nodes configured to read this
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, it could be possible to
consider a non-conventional application of the Destination Options
for hop by hop action, but this would cause worse performance than
Hop-by-Hop. The only motivation for the hop by hop usage of
Destination Options can be for compatibility reasons but in general
it is not recommended.
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5. Alternate Marking Method Operation
This section describes how the method operates. [RFC8321] introduces
several alternatives but in this section the most applicable methods
are reported and a new field is introduced to facilitate the
deployment and improve the scalability.
5.1. Packet Loss Measurement
The measurement of the packet loss is really straightforward. The
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
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 this depends on the implementation. By counting the number of
packets in each batch and comparing the values measured by different
network nodes along the path, it is possible to measure the packet
loss occurred in any single batch between any two nodes. Each batch
represents a measurable entity unambiguously recognizable by all
network nodes along the path.
Packets with different L values may get swapped at batch boundaries,
and in this case, it is required that each marked packet can be
assigned to the right batch by each router. It is important to
mention that for the application of this method there are two
elements to consider: the clock error between network nodes and the
network delay. These can create offsets between the batches and out-
of-order of the packets. There is the condition on timing aspects
explained in [RFC8321] that must be satisfied and it takes into
considerations the different causes of reordering such as clock
error, network delay. The consequence is that it is necessary to
define a waiting interval where to get stable counters and to avoid
these issues. Usually the counters can be taken in the middle of the
batch period to be sure to take still counters. In a few words this
implies that the length of the batches MUST be chosen large enough so
that the method is not affected by those factors.
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L bit=1 ----------+ +-----------+ +----------
| | | |
L bit=0 +-----------+ +-----------+
Batch n ... Batch 3 Batch 2 Batch 1
<---------> <---------> <---------> <---------> <--------->
Traffic Flow
===========================================================>
L bit ...1111111111 0000000000 11111111111 00000000000 111111111...
===========================================================>
Figure 1: Packet Loss Measurement and Single-Marking Methodology
using L bit
5.2. Packet Delay Measurement
The same principle used to measure packet loss can be applied also to
one-way delay measurement. Delay metrics MAY be calculated using the
two possibilities:
1. Single-Marking Methodology: This approach uses only the L bit to
calculate both packet loss and delay. In this case, the D flag
MUST be set to zero on transmit and ignored by the monitoring
points. The alternation of the values of the L bit can be used
as a time reference to calculate the delay. Whenever the L bit
changes and a new batch starts, a network node can store the
timestamp of the first packet of the new batch, that timestamp
can be compared with the timestamp of the first packet of the
same batch on a second node to compute packet delay. Anyway this
measurement is accurate only if no packet loss occurs and if
there is no packet reordering at the edges of the batches. A
different approach can also be considered and it is based on the
concept of the mean delay. The mean delay for each batch is
calculated by considering the average arrival time of the packets
for the relative batch. There are limitations also in this case
indeed, each node needs to collect all the timestamps and
calculate the average timestamp for each batch. In addition the
information is limited to a mean value.
2. Double-Marking Methodology: This approach is more complete and
uses the L bit only to calculate packet loss and the D bit (Delay
flag) is fully dedicated to delay measurements. The idea is to
use the first marking with the L bit to create the alternate flow
and, within the batches identified by the L bit, a second marking
is used to select the packets for measuring delay. The D bit
creates a new set of marked packets that are fully identified
over the network, so that a network node can store the timestamps
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of these packets; these timestamps can be compared with the
timestamps of the same packets on a second node to compute packet
delay values for each packet. The most efficient and robust mode
is to select a single double-marked packet for each batch, in
this way there is no time gap to consider between the double-
marked packets to avoid their reorder. If a double-marked packet
is lost, the delay measurement for the considered batch is simply
discarded, but this is not a big problem because it is easy to
recognize the problematic batch and skip the measurement just for
that one. So in order to have more information about the delay
and to overcome out-of-order issues this method is preferred.
L bit=1 ----------+ +-----------+ +----------
| | | |
L bit=0 +-----------+ +-----------+
D bit=1 + + + + +
| | | | |
D bit=0 ------+----------+----------+----------+------------+-----
Traffic Flow
===========================================================>
L bit ...1111111111 0000000000 11111111111 00000000000 111111111...
D bit ...0000010000 0000010000 00000100000 00001000000 000001000...
===========================================================>
Figure 2: Double-Marking Methodology using L bit and D bit
Similar to packet delay measurement (both for Single Marking and
Double Marking), the method can also be used to measure the inter-
arrival jitter.
5.3. Flow Monitoring Identification
The Flow Monitoring Identification (FlowMonID) is required for some
general reasons:
o First, it helps to reduce the per node configuration. Otherwise,
each node needs to configure an access-control list (ACL) for each
of the monitored flows. Moreover, using a flow identifier allows
a flexible granularity for the flow definition.
o Second, it simplifies the counters handling. Hardware processing
of flow tuples (and ACL matching) is challenging and often incurs
into performance issues, especially in tunnel interfaces.
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o Third, it eases the data export encapsulation and correlation for
the collectors.
The FlowMon identifier field is to uniquely identify a monitored flow
within the measurement domain. The field is set at the source node.
The FlowMonID can be uniformly assigned by the central controller or
algorithmically generated by the source node. The latter approach
cannot guarantee the uniqueness of FlowMonID but it may be preferred
for local or private network, where the conflict probability is small
due to the large FlowMonID space.
5.3.1. Uniqueness of FlowMonID
It is important to note that if the 20 bit FlowMonID is set
independently and pseudo randomly there is a chance of collision.
So, in some cases, FlowMonID could not be sufficient for uniqueness.
In general the probability of a flow identifier uniqueness correlates
to the amount of entropy of the inputs. For instance, using the
well-known birthday problem in probability theory, if the 20 bit
FlowMonID is set independently and pseudo randomly without any
additional input entropy, there is a 50% chance of collision for just
1206 flows. For a 32 bit identifier the 50% threshold jumps to
77,163 flows and so on. So, for more entropy, FlowMonID can either
be combined with other identifying flow information in a packet (e.g.
it is possible to consider the hashed 3-tuple Flow Label, Source and
Destination addresses) or the FlowMonID size could be increased.
This issue is more visible when the FlowMonID is pseudo randomly
generated by the source node and there needs to tag it with
additional flow information to allow disambiguation. While, in case
of a centralized controller, the controller should set FlowMonID by
considering these aspects and instruct the nodes properly in order to
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.
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5.4. Multipoint and Clustered Alternate Marking
The Alternate Marking method can also be extended to any kind of
multipoint to multipoint paths, and the network clustering approach
allows a flexible and optimized performance measurement, as described
in [RFC8889].
The Cluster is the smallest identifiable subnetwork of the entire
Network graph that still satisfies the condition that the number of
packets that goes in is the same that goes out. With network
clustering, it is possible to use the partition of the network into
clusters at different levels in order to perform the needed degree of
detail. So, for Multipoint Alternate Marking, FlowMonID can identify
in general a multipoint-to-multipoint flow and not only a point-to-
point flow.
5.5. Data Collection and Calculation
The nodes enabled to perform performance monitoring collect the value
of the packet counters and timestamps. There are several
alternatives to implement Data Collection and Calculation, but this
is not specified in this document.
6. Security Considerations
This document aims to apply a method to perform measurements that
does not directly affect Internet security nor applications that run
on the Internet. However, implementation of this method must be
mindful of security and privacy concerns.
There are two types of security concerns: potential harm caused by
the measurements and potential harm to the measurements.
Harm caused by the measurement: Alternate Marking implies
modifications on the fly to an Option Header of IPv6 packets by the
source node but this must be performed in a way that does not alter
the quality of service experienced by the packets and that preserves
stability and performance of routers doing the measurements. The
advantage of the Alternate Marking method is that the marking bits
are the only information that is exchanged between the network nodes.
Therefore, network reconnaissance through passive eavesdropping on
data-plane traffic does not allow attackers to gain information about
the network performance. Moreover, Alternate Marking should usually
be applied in a controlled domain and this also helps to limit the
problem.
Harm to the Measurement: Alternate Marking measurements could be
harmed by routers altering the marking of the packets or by an
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attacker injecting artificial traffic. Since the measurement itself
may be affected by network nodes along the path intentionally
altering the value of the marking bits of IPv6 packets, the Alternate
Marking should be applied in the context of a controlled domain,
where the network nodes are locally administered and this type of
attack can be avoided. Indeed the source and destination addresses
are within the controlled domain and therefore it is unlikely subject
to hijacking of packets, because it is possible to filter external
packets at the domain boundaries. In addition, an attacker cannot
gain information about network performance from a single monitoring
point; it must use synchronized monitoring points at multiple points
on the path, because they have to do the same kind of measurement and
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
method only relies on information contained in the Option Header
without any release of user data. Although information in the Option
Header is metadata that can be used to compromise the privacy of
users, the limited marking technique seems unlikely to substantially
increase the existing privacy risks from header or encapsulation
metadata.
The Alternate Marking application described in this document relies
on an time synchronization protocol. Thus, by attacking the time
protocol, an attacker can potentially compromise the integrity of the
measurement. A detailed discussion about the threats against time
protocols and how to mitigate them is presented in [RFC7384].
7. IANA Considerations
The Option Type should be assigned in IANA's "Destination Options and
Hop-by-Hop Options" registry.
This draft requests the following IPv6 Option Type assignments from
the Destination Options and Hop-by-Hop Options sub-registry of
Internet Protocol Version 6 (IPv6) Parameters
(https://www.iana.org/assignments/ipv6-parameters/).
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Hex Value Binary Value Description Reference
act chg rest
----------------------------------------------------------------
TBD 00 0 tbd AltMark [This draft]
8. Acknowledgements
The authors would like to thank Bob Hinden, Ole Troan, Tom Herbert,
Stefano Previdi, Brian Carpenter, Eric Vyncke, Ron Bonica, Greg
Mirsky for the precious comments and suggestions.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[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>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
9.2. Informative References
[I-D.fioccola-v6ops-ipv6-alt-mark]
Fioccola, G., Velde, G., Cociglio, M., and P. Muley, "IPv6
Performance Measurement with Alternate Marking Method",
draft-fioccola-v6ops-ipv6-alt-mark-01 (work in progress),
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
Architecture", RFC 4291, DOI 10.17487/RFC4291, February
2006, <https://www.rfc-editor.org/info/rfc4291>.
Fioccola, et al. Expires September 9, 2021 [Page 14]
Internet-Draft IPv6 AMM March 2021
[RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", RFC 6437,
DOI 10.17487/RFC6437, November 2011,
<https://www.rfc-editor.org/info/rfc6437>.
[RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing
of IPv6 Extension Headers", RFC 7045,
DOI 10.17487/RFC7045, December 2013,
<https://www.rfc-editor.org/info/rfc7045>.
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384,
October 2014, <https://www.rfc-editor.org/info/rfc7384>.
[RFC8321] Fioccola, G., Ed., Capello, A., Cociglio, M., Castaldelli,
L., Chen, M., Zheng, L., Mirsky, G., and T. Mizrahi,
"Alternate-Marking Method for Passive and Hybrid
Performance Monitoring", RFC 8321, DOI 10.17487/RFC8321,
January 2018, <https://www.rfc-editor.org/info/rfc8321>.
[RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
<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,
"Multipoint Alternate-Marking Method for Passive and
Hybrid Performance Monitoring", RFC 8889,
DOI 10.17487/RFC8889, August 2020,
<https://www.rfc-editor.org/info/rfc8889>.
Authors' Addresses
Giuseppe Fioccola
Huawei
Riesstrasse, 25
Munich 80992
Germany
Email: giuseppe.fioccola@huawei.com
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Tianran Zhou
Huawei
156 Beiqing Rd.
Beijing 100095
China
Email: zhoutianran@huawei.com
Mauro Cociglio
Telecom Italia
Via Reiss Romoli, 274
Torino 10148
Italy
Email: mauro.cociglio@telecomitalia.it
Fengwei Qin
China Mobile
32 Xuanwumenxi Ave.
Beijing 100032
China
Email: qinfengwei@chinamobile.com
Ran Pang
China Unicom
9 Shouti South Rd.
Beijing 100089
China
Email: pangran@chinaunicom.cn
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