MBONED H. Song
Internet-Draft M. McBride
Intended status: Standards Track Futurewei Technologies
Expires: January 7, 2022 G. Mirsky
ZTE Corp.
G. Mishra
Verizon Inc.
H. Asaeda
NICT
T. Zhou
Huawei
July 6, 2021
Multicast On-path Telemetry Solutions
draft-ietf-mboned-multicast-telemetry-01
Abstract
This document discusses the requirement of on-path telemetry for
multicast traffic. The existing solutions are examined and their
issues are identified. Solution modifications are proposed to allow
the original multicast tree to be correctly reconstructed without
unnecessary replication of telemetry information.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "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."
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This Internet-Draft will expire on January 7, 2022.
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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements for Multicast Traffic Telemetry . . . . . . . . 3
3. Issues of Existing Techniques . . . . . . . . . . . . . . . . 4
4. Proposed Modifications to Existing Techniques . . . . . . . . 5
4.1. Per-hop postcard using IOAM DEX . . . . . . . . . . . . . 5
4.2. Per-section postcard . . . . . . . . . . . . . . . . . . 7
5. Considerations for Different Multicast Protocols . . . . . . 8
5.1. Application in PIM . . . . . . . . . . . . . . . . . . . 8
5.2. Application of MVPN X-PMSI Tunnel Encapsulation Attribute 9
5.3. Application in BIER . . . . . . . . . . . . . . . . . . . 9
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 10
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
10.1. Normative References . . . . . . . . . . . . . . . . . . 10
10.2. Informative References . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
Multicast traffic is used across operator networks to support
residential broadband customers, private MPLS customers and used with
corporate intranet internal customers. Multicast provides real time
interactive online meetings or podcasts, IPTV and financial markets
real-time data, which all have a reliance on UDP's unreliable
transport. End to end QOS, therefore, should be a critical component
of multicast deployment in order to provide a good end user viewing
experience. If a packet is dropped, and that packet happens to be a
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reference frame (I-Frame) in the video feed, the client receiver of
the multicast feed goes into buffering mode resulting in a frozen
window. Multicast packet drops and delay can severely affect the
application performance and user experience.
It is important to monitor the performance of the multicast traffic.
New on-path telemetry techniques such as In-situ OAM
[I-D.ietf-ippm-ioam-data], Postcard-based Telemetry
[I-D.song-ippm-postcard-based-telemetry], and Hybrid Two-Step (HTS)
[I-D.mirsky-ippm-hybrid-two-step] are useful and complementary to the
existing active OAM performance monitoring methods, provide promising
means to directly monitor the network experience of multicast
traffic. However, multicast traffic has some unique characteristics
which pose some challenges on efficiently applying such techniques.
The IP Multicast S,G data is identical from one branch to another on
it's way to multiple receivers. When adding iOAM trace data, to
multicast packets, we enlarge data packets thus consuming more
network bandwidth. Instead of adding iOAM trace data, it could be
more efficient to collect the telemetry information using solutions,
such as iOAM postcard or HTS, to cut down on the redundant iOAM data.
The problem is that a postcard type solution doesn't have a branch
identifier.
This draft proposes a set of solutions to this iOAM data redundancy
problem. The requirements for multicast traffic telemetry are
discussed along with the issues of the existing on-path telemetry
techniques. We propose modifications to make these techniques adapt
to multicast in order for the original multicast tree to be correctly
reconstructed while eliminating redundant data.
2. Requirements for Multicast Traffic Telemetry
Multicast traffic is forwarded through a multicast tree. With PIM
and P2MP (MLDP, RSVP-TE) the forwarding tree is established and
maintained by the multicast routing protocol. With BIER, no state is
created in the network to establish a forwarding tree, instead, a
bier header provides the necessary information for each packet to
know the egress points. Multicast packets are only replicated at
each tree branch node for efficiency.
There are several requirements for multicast traffic telemetry, a few
of which are:
o Reconstruct and visualize the multicast tree through data plane
monitoring.
o Gather the multicast packet delay and jitter performance.
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o Find the multicast packet drop location and reason.
o Gather the VPN state and tunnel information in case of P2MP
multicast.
In order to meet these requirements, we need the ability to directly
monitor the multicast traffic and derive data from the multicast
packets. The conventional OAM mechanisms, such as multicast ping and
trace, may not be sufficient to meet these requirements.
3. Issues of Existing Techniques
On-path Telemetry techniques that directly retrieve data from
multicast traffic's live network experience are ideal to address the
above mentioned requirements. The representative techniques include
In-situ OAM (IOAM) Trace option [I-D.ietf-ippm-ioam-data], IOAM
Direct Export (DEX) option [I-D.ioamteam-ippm-ioam-direct-export],
and Postcard-based Telemetry with Packet Marking(PBT-M)
[I-D.song-ippm-postcard-based-telemetry]. However, unlike unicast,
multicast poses some unique challenges to applying these techniques.
Multicast packets are replicated at each branch node in the
corresponding multicast tree. Therefore, there are multiple copies
of packets in the network.
If the IOAM trace option is used for on-path data collection, the
partial trace data will also be replicated into multiple copies. The
end result is that each copy of the multicast packet has a complete
trace. Most of the data, however, is redundant. Data redundancy
introduces unnecessary header overhead, wastes network bandwidth, and
complicates the data processing. In case the multicast tree is
large, and the path is long, the redundancy problem becomes severe.
The PBT solutions, including the IOAM DEX option and PBT-M, can be
used to eliminate such data redundancy, because each node on the tree
only sends a postcard covering local data. However, they cannot
track the tree branches properly so it can bring confusion about the
multicast tree topology. For example, Node A has two branches, one
to Node B and the other to node D, and Node B leads to Node C and
Node D leads to Node E. From the received postcards, one cannot tell
whether or not Node C(E) is the next hop of Node B(D).
The fundamental reason for this problem is that there is not an
identifier (either implicit or explicit) to correlate the data on
each branch.
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4. Proposed Modifications to Existing Techniques
Two solutions are proposed to address the above issues. One is built
on PBT and requires augmentation or modification to the instruction
header of the IOAM Direct Export Option; the other combines the IOAM
trace option and PBT for an optimized solution.
4.1. Per-hop postcard using IOAM DEX
One way to mitigate PBT's multiple tree tracking weakness is to
augment it with a branch identifier field. Note that this works for
the IOAM DEX option but not for PBT-M because the IOAM DEX option
uses an instruction header. To make the branch identifier globally
unique, the branch node ID plus an index is used. For example, if
Node A has two branches, one to Node B and one to Node C, Node A will
use [A, 0] as the branch identifier for the branch to B, and [A, 1]
for the branch to C. The identifier is unchanged for each multicast
tree instance and carried with the multicast packet until the next
branch node. Each postcard needs to include the branch identifier in
the export data. The branch identifier, along with the other fields
such as flow ID and sequence number, is sufficient for the data
analyzer to reconstruct the topology of the multicast tree.
Figure 1 shows an example of this solution. "P" stands for the
postcard packet. The square brackets contains the branch identifier.
The curly brace contains the telemetry data about a specific node.
P:[A,0]{A} P:[A,0]{B} P:[B,1]{D} P:[B,0]{C}
^ ^ ^ ^
: : : :
: : : :
: : : +-:-+
: : : | |
: : +---:----->| C |--...
+-:-+ +-:-+ | : | |
| | | |----+ : +---+
| A |------->| B | :
| | | |--+ +-:-+
+---+ +---+ | | |
+-->| D |--....
| |
+---+
Figure 1: Per-hop Postcard
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Each branch fork node needs to generate the branch ID for each branch
in its multicast tree instance and include it in the IOAM DEX option
header so the downstream node can learn it. The branch ID contains
two parts: the branch fork node ID and a unique branch index.
Figure 2 shows that the branch ID is carried as an optional field
after the flow ID and sequence number optional fields in the IOAM DEX
option header. A bit "M" in the Flags field is reserved to indicate
the presence of the branch index field. The "M" flag position will
be determined later after the other flags are specified in
[I-D.ioamteam-ippm-ioam-direct-export].
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID |M| Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow ID (optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number (Optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Encoded Branch ID (optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Carry Branch Index in IOAM DEX option header
To avoid introducing a new type of data field to the IOAM DEX option
header, we can encode the branch identifier using the existing node
ID data field as defined in [I-D.ietf-ippm-ioam-data]. Currently,
the node ID field occupies three octets. A simple solution is to
shorten the node ID field so a number of bits can be saved to encode
the branch index, as shown in Figure 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id | branch index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Encode Branch Index with Node ID Method 1
Another encoding method is to use the sum of the node ID and the
branch index as the new node ID, as shown in Figure 4. As long as
the node IDs are assigned with large enough gap, the telemetry data
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analyzer can still successfully recover the original node ID and
branch index.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id + branch index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Encode Branch Index with Node ID Method 2
Once a node gets the branch ID information from the upstream, it MUST
carry this information in its telemetry data export postcards, so the
original multicast tree can be correctly reconstructed based on the
postcards.
4.2. Per-section postcard
The second solution is a combination of the IOAM trace mode and PBT.
To avoid data redundancy at each branch node, the trace data
accumulated, to that point, is exported by a postcard before the
packet is replicated. In this case, each branch still needs to
maintain some identifier to help correlate the postcards for each
tree section. The natural way to accomplish this is to simply carry
the branch node's data (including its ID) in the trace of each
branch. This is also necessary because each replicated multicast
packet can have different telemetry data pertaining to this
particular copy (e.g., node delay, egress timestamp, and egress
interface). As a consequence, the local data exported by each branch
node can only contain partial data (e.g., ingress interface and
ingress timestamp).
Figure 5 shows an example in a segment of a multicast tree. Node B
and D are two branch nodes and they will export a postcard covering
the trace data for the previous section. The end node of each path
will also need to export the data of the last section as a postcard.
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P:{A,B'} P:{B1,C,D'}
^ ^
: :
: :
: : {D1}
: : +--...
: +---+ +---+ |
: {B1} | |{B1,C}| |--+ {D2}
: +-->| C |----->| D |-----...
+---+ +---+ | | | | |--+
| | {A} | |--+ +---+ +---+ |
| A |---->| B | +--...
| | | |--+ +---+ {D3}
+---+ +---+ | | |{B2,E}
+-->| E |--...
{B2} | |
+---+
Figure 5: Per-section Postcard
There is no need to modify the IOAM trace mode header format. We
just need to configure the branch node to export the postcard and
refresh the IOAM header and data.
5. Considerations for Different Multicast Protocols
MTRACEv2 [RFC8487] provides an active probing approach for the
tracing of an IP multicast routing path. Mtrace can also provide
information such as the packet rates and losses, as well as other
diagnostic information. New on-path telemetry techniques will
enhance Mtrace, and other existing OAM solutions, with more granular
and realtime network status data through direct measurements. There
are various multicast protocols that are used to forward the
multicast data. Each will require their own unique on-path telemetry
solution.
5.1. Application in PIM
PIM-SM [RFC7761] is the most widely used multicast routing protocol
deployed today. Of the various PIM modes (PIM-SM, PIM-DM, BIDIR-PIM,
PIM-SSM), PIM-SSM is the preferred method due to its simplicity and
removal of network source discovery complexity. With all PIM modes,
control plane state is established in the network in order to forward
multicast UDP data packets. All PIM modes utilize network based
source discovery except for PIM-SSM, which utilizes application based
source discovery. IP Multicast packets fall within the range of
224.0.0.0 through 239.255.255.255. The telemetry solution will need
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to work within this address range and provide telemetry data for this
UDP traffic.
The proposed solutions for encapsulating the telemetry instruction
header and metadata in IPv4/IPv6 UDP packets are described in
[I-D.herbert-ipv4-udpencap-eh] and
[I-D.ioametal-ippm-6man-ioam-ipv6-deployment].
5.2. Application of MVPN X-PMSI Tunnel Encapsulation Attribute
Multipoint Label Distribution Protocol (mLDP), P2MP RSVP-TE, Ingress
Replication (IR), PIM MDT SAFI with GRE Transport, are commonly used
within a Multicast VPN (MVPN) environment utilizing MVPN procedures
Multicast in MPLS/BGP IP VPNs [RFC6513] and BGP Encoding and
Procedures for Multicast in MPLS/BGP IP VPNs [RFC6514]. MLDP LDP
Extension for P2MP and MP2MP LSPs [RFC6388] provides extensions to
LDP to establish point-to-multipoint (P2MP) and multipoint-to-
multipoint (MP2MP) label switched paths (LSPs) in MPLS networks.
P2MP RSVP-TE provides extensions to RSVP-TE RSVP-TE for P2MP LSPs
[RFC4875] for establish traffic-engineered P2MP LSPs in MPLS
networks. Ingress Replication (IR) P2MP Trees Ingress Replication
Tunnels in Multicast VPNs [RFC7988] using unicast replication from
parent node to child node over MPLS Unicast Tunnel. PIM MDT SAFI
Multicast in BGP/MPLS IP VPNs [RFC6037]utilizes PIM modes PIM-SSM,
PIM-SM, PIM-BIDIR control plane with GRE transport data plane in the
core for X-PMSI P-Tree using MVPN procedures. Replication SID SR
Replication Segment for Multi-point Service Delivery
[I-D.ietf-spring-sr-replication-segment] replication segments for
P2MP multicast service delivery in Segment Routing SR-MPLS networks.
The telemetry solution will need to be able to follow these P2MP and
MP2MP paths. The telemetry instruction header and data should be
encapsulated into MPLS packets on P2MP and MP2MP paths. A
corresponding proposal is described in
[I-D.song-mpls-extension-header].
5.3. Application in BIER
BIER [RFC8279] adds a new header to multicast packets and allows the
multicast packets to be forwarded according to the header only. By
eliminating the requirement of maintaining per multicast group state,
BIER is more scalable than the traditional multicast solutions.
OAM Requirements for BIER [I-D.ietf-bier-oam-requirements] lists many
of the requirements for OAM at the BIER layer which will help in the
forming of on-path telemetry requirements as well.
There is also current work to provide solutions for BIER forwarding
in ipv6 networks. For instance, a solution, BIER in Non-MPLS IPv6
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Networks [I-D.xie-bier-ipv6-encapsulation], proposes a new bier
Option Type codepoint from the "Destination Options and Hop-by-Hop
Options" IPv6 sub-registry. This is similar to what IOAM proposes
for IPv6 transport.
Depending on how the BIER header is encapsulated into packets with
different transport protocols, the method to encapsulate the
telemetry instruction header and metadata also varies. It is also
possible to make the instruction header and metadata a part of the
BIER header itself, such as in a TLV.
6. Security Considerations
No new security issues are identified other than those discovered by
the IOAM, PBT and HTS drafts.
7. IANA Considerations
The document makes no request of IANA.
8. Contributors
TBD
9. Acknowledgments
The authors would like to thank Frank Brockners for the comments and
advice.
10. References
10.1. 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>.
[RFC4687] Yasukawa, S., Farrel, A., King, D., and T. Nadeau,
"Operations and Management (OAM) Requirements for Point-
to-Multipoint MPLS Networks", RFC 4687,
DOI 10.17487/RFC4687, September 2006,
<https://www.rfc-editor.org/info/rfc4687>.
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[RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
Yasukawa, Ed., "Extensions to Resource Reservation
Protocol - Traffic Engineering (RSVP-TE) for Point-to-
Multipoint TE Label Switched Paths (LSPs)", RFC 4875,
DOI 10.17487/RFC4875, May 2007,
<https://www.rfc-editor.org/info/rfc4875>.
[RFC6037] Rosen, E., Ed., Cai, Y., Ed., and IJ. Wijnands, "Cisco
Systems' Solution for Multicast in BGP/MPLS IP VPNs",
RFC 6037, DOI 10.17487/RFC6037, October 2010,
<https://www.rfc-editor.org/info/rfc6037>.
[RFC6388] Wijnands, IJ., Ed., Minei, I., Ed., Kompella, K., and B.
Thomas, "Label Distribution Protocol Extensions for Point-
to-Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, DOI 10.17487/RFC6388, November 2011,
<https://www.rfc-editor.org/info/rfc6388>.
[RFC6513] Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
BGP IP VPNs", RFC 6513, DOI 10.17487/RFC6513, February
2012, <https://www.rfc-editor.org/info/rfc6513>.
[RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
Encodings and Procedures for Multicast in MPLS/BGP IP
VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
<https://www.rfc-editor.org/info/rfc6514>.
[RFC7761] Fenner, B., Handley, M., Holbrook, H., Kouvelas, I.,
Parekh, R., Zhang, Z., and L. Zheng, "Protocol Independent
Multicast - Sparse Mode (PIM-SM): Protocol Specification
(Revised)", STD 83, RFC 7761, DOI 10.17487/RFC7761, March
2016, <https://www.rfc-editor.org/info/rfc7761>.
[RFC7988] Rosen, E., Ed., Subramanian, K., and Z. Zhang, "Ingress
Replication Tunnels in Multicast VPN", RFC 7988,
DOI 10.17487/RFC7988, October 2016,
<https://www.rfc-editor.org/info/rfc7988>.
[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>.
[RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
Explicit Replication (BIER)", RFC 8279,
DOI 10.17487/RFC8279, November 2017,
<https://www.rfc-editor.org/info/rfc8279>.
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[RFC8487] Asaeda, H., Meyer, K., and W. Lee, Ed., "Mtrace Version 2:
Traceroute Facility for IP Multicast", RFC 8487,
DOI 10.17487/RFC8487, October 2018,
<https://www.rfc-editor.org/info/rfc8487>.
10.2. Informative References
[I-D.herbert-ipv4-udpencap-eh]
Herbert, T., "IPv4 Extension Headers and UDP Encapsulated
Extension Headers", draft-herbert-ipv4-udpencap-eh-01
(work in progress), March 2019.
[I-D.ietf-bier-oam-requirements]
Mirsky, G., Kumar, N., Chen, M., and S. Pallagatti,
"Operations, Administration and Maintenance (OAM)
Requirements for Bit Index Explicit Replication (BIER)
Layer", draft-ietf-bier-oam-requirements-11 (work in
progress), November 2020.
[I-D.ietf-ippm-ioam-data]
Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
for In-situ OAM", draft-ietf-ippm-ioam-data-12 (work in
progress), February 2021.
[I-D.ietf-spring-sr-replication-segment]
Voyer, D., Filsfils, C., Parekh, R., Bidgoli, H., and Z.
Zhang, "SR Replication Segment for Multi-point Service
Delivery", draft-ietf-spring-sr-replication-segment-04
(work in progress), February 2021.
[I-D.ioametal-ippm-6man-ioam-ipv6-deployment]
Bhandari, S., Brockners, F., Mizrahi, T., Kfir, A., Gafni,
B., Spiegel, M., Krishnan, S., and M. Smith, "Deployment
Considerations for In-situ OAM with IPv6 Options", draft-
ioametal-ippm-6man-ioam-ipv6-deployment-03 (work in
progress), March 2020.
[I-D.ioamteam-ippm-ioam-direct-export]
Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F.,
Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ
OAM Direct Exporting", draft-ioamteam-ippm-ioam-direct-
export-00 (work in progress), October 2019.
[I-D.mirsky-ippm-hybrid-two-step]
Mirsky, G., Lingqiang, W., Zhui, G., and H. Song, "Hybrid
Two-Step Performance Measurement Method", draft-mirsky-
ippm-hybrid-two-step-09 (work in progress), March 2021.
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[I-D.song-ippm-postcard-based-telemetry]
Song, H., Mirsky, G., Filsfils, C., Abdelsalam, A., Zhou,
T., Li, Z., Shin, J., and K. Lee, "Postcard-based On-Path
Flow Data Telemetry using Packet Marking", draft-song-
ippm-postcard-based-telemetry-09 (work in progress),
February 2021.
[]
Song, H., Li, Z., Zhou, T., and L. Andersson, "MPLS
Extension Header", draft-song-mpls-extension-header-04
(work in progress), April 2021.
[I-D.xie-bier-ipv6-encapsulation]
Xie, J., Geng, L., McBride, M., Asati, R., Dhanaraj, S.,
Zhu, Y., Qin, Z., Shin, M., Mishra, G., and X. Geng,
"Encapsulation for BIER in Non-MPLS IPv6 Networks", draft-
xie-bier-ipv6-encapsulation-10 (work in progress),
February 2021.
Authors' Addresses
Haoyu Song
Futurewei Technologies
2330 Central Expressway
Santa Clara
USA
Email: hsong@futurewei.com
Mike McBride
Futurewei Technologies
2330 Central Expressway
Santa Clara
USA
Email: mmcbride@futurewei.com
Greg Mirsky
ZTE Corp.
Email: gregimirsky@gmail.com
Song, et al. Expires January 7, 2022 [Page 13]
Internet-Draft Multicast Telemetry July 2021
Gyan Mishra
Verizon Inc.
Email: gyan.s.mishra@verizon.com
Hitoshi Asaeda
National Institute of Information and Communications Technology
4-2-1 Nukui-Kitamachi
Koganei, Tokyo 184-8795
Japan
Email: asaeda@nict.go.jp
Tianran Zhou
Huawei
Email: zhoutianran@huawei.com
Song, et al. Expires January 7, 2022 [Page 14]