One-Way and Two-Way Active Measurement Protocol Extensions for Performance Measurement on a Link Aggregation Group
RFC 9533
| Document | Type | RFC - Proposed Standard (January 2024) | |
|---|---|---|---|
| Authors | Zhenqiang Li , Tianran Zhou , Guo Jun , Greg Mirsky , Rakesh Gandhi | ||
| Last updated | 2024-01-31 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| IESG | Responsible AD | Martin Duke | |
| Send notices to | (None) |
RFC 9533
Internet Engineering Task Force (IETF) Z. Li
Request for Comments: 9533 China Mobile
Category: Standards Track T. Zhou
ISSN: 2070-1721 Huawei
J. Guo
ZTE Corp.
G. Mirsky
Ericsson
R. Gandhi
Cisco Systems, Inc.
January 2024
One-Way and Two-Way Active Measurement Protocol Extensions for
Performance Measurement on a Link Aggregation Group
Abstract
This document defines extensions to the One-Way Active Measurement
Protocol (OWAMP) and the Two-Way Active Measurement Protocol (TWAMP)
to implement performance measurement on every member link of a Link
Aggregation Group (LAG). Knowing the measured metrics of each member
link of a LAG enables operators to enforce the performance-based
traffic steering policy across the member links.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9533.
Copyright Notice
Copyright (c) 2024 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
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Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction
1.1. Requirements Language
2. Micro Sessions on a LAG
3. Micro OWAMP Session
3.1. Micro OWAMP-Control
3.2. Micro OWAMP-Test
4. Micro TWAMP Session
4.1. Micro TWAMP-Control
4.2. Micro TWAMP-Test
4.2.1. Sender Packet Format and Content
4.2.2. Sender Behavior
4.2.3. Reflector Packet Format and Content
4.2.4. Reflector Behavior
5. Applicability
6. IANA Considerations
6.1. Micro OWAMP-Control Command
6.2. Micro TWAMP-Control Command
7. Security Considerations
8. References
8.1. Normative References
8.2. Informative References
Acknowledgements
Authors' Addresses
1. Introduction
A Link Aggregation Group (LAG), as defined in [IEEE802.1AX], provides
mechanisms to combine multiple physical links into a single logical
link. This logical link offers higher bandwidth and better
resiliency because, if one of the physical member links fails, the
aggregate logical link can continue to forward traffic over the
remaining operational physical member links.
Usually, when forwarding traffic over a LAG, a hash-based mechanism
is used to load balance the traffic across the LAG member links. The
link delay might vary between member links because of different
transport paths, especially when a LAG is used in a wide area
network. To provide low-latency service for time-sensitive traffic,
we need to explicitly steer the traffic across the LAG member links
based on the link delay, loss, and so on. That requires a solution
to measure the performance metrics of every member link of a LAG.
Hence, the measured performance metrics can work together with Layer
2 bundle member link attributes advertisement [RFC8668] for traffic
steering.
According to the classifications in [RFC7799], OWAMP [RFC4656] and
TWAMP [RFC5357] are active measurement methods, and they can
complement passive and hybrid methods. With either method, one test
session over the LAG can be used to measure the performance of a
member link using a specially constructed 5-tuple. The session can
be used to measure an average of some or all member links of the LAG
by varying one or more elements of that 5-tuple. However, without
the knowledge of each member link, a test session cannot measure the
performance of every physical member link.
This document extends OWAMP and TWAMP to implement performance
measurement on every member link of a LAG. It can provide the same
metrics as OWAMP and TWAMP can measure, such as delay, jitter, and
packet loss.
1.1. 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.
2. Micro Sessions on a LAG
This document addresses the scenario where a LAG directly connects
two nodes. An example of this is in Figure 1, where the LAG
consisting of four links connects nodes A and B. The goal is to
measure the performance of each link of the LAG.
+---+ +---+
| |-----------------------| |
| A |-----------------------| B |
| |-----------------------| |
| |-----------------------| |
+---+ +---+
Figure 1: Performance Measurement on a LAG
To measure the performance metrics of every member link of a LAG,
multiple sessions (one session for each member link) need to be
established between the two endpoints that are connected by the LAG.
These sessions are called "micro sessions" in the remainder of this
document. Although micro sessions are in fact OWAMP or TWAMP
sessions established on member links of a LAG, test packets of micro
TWAMP sessions MUST carry member link information for validation.
All micro sessions of a LAG share the same Sender IP Address and
Receiver IP Address. As for the UDP port, the micro sessions may
share the same Sender Port and Receiver Port pair or each micro
session may be configured with a different Sender Port and Receiver
Port pair. From the operational point of view, the former is simpler
and is RECOMMENDED.
Test packets of a micro session MUST carry the member link
information for validation checks. For example, when a micro TWAMP
Session-Sender receives a reflected test packet, it checks whether
the test packet is from the expected member link.
3. Micro OWAMP Session
3.1. Micro OWAMP-Control
To support the micro OWAMP session, a new command, Request-OW-Micro-
Sessions (5), is defined in this document. The Request-OW-Micro-
Sessions command is based on the OWAMP Request-Session command and
uses the message format as described in Section 3.5 of [RFC4656].
Test session creation of micro OWAMP sessions follows the same
procedure as defined in Section 3.5 of [RFC4656] with the following
additions:
When an OWAMP Server receives a Request-OW-Micro-Sessions command, if
the request is accepted, the OWAMP Server MUST build a set of micro
sessions for all the member links of the LAG from which the Request-
OW-Micro-Sessions message is received.
3.2. Micro OWAMP-Test
Micro OWAMP-Test reuses the OWAMP-Test packet format and procedures
as defined in Section 4 of [RFC4656] with the following additions:
The micro OWAMP Session-Sender MUST send the micro OWAMP-Test packets
over the member link with which the session is associated. When it
receives a test packet, the micro OWAMP Session-Receiver MUST use the
member link from which the test packet is received to correlate the
micro OWAMP session. If there is no such session, the test packet
MUST be discarded.
4. Micro TWAMP Session
4.1. Micro TWAMP-Control
To support the micro TWAMP session, a new command, Request-TW-Micro-
Sessions (11), is defined in this document. The Request-TW-Micro-
Sessions command is based on the TWAMP Request-Session command and
uses the message format as described in Section 3.5 of [RFC5357].
Test session creation of micro TWAMP sessions follows the same
procedure as defined in Section 3.5 of [RFC5357] with the following
additions:
When a TWAMP Server receives a Request-TW-Micro-Sessions command, if
the request is accepted, the TWAMP Server MUST build a set of micro
sessions for all the member links of the LAG from which the Request-
TW-Micro-Sessions message is received.
4.2. Micro TWAMP-Test
The micro TWAMP-Test protocol is based on the TWAMP-Test protocol
[RFC5357] with the extensions described in the following subsections.
4.2.1. Sender Packet Format and Content
The micro TWAMP Session-Sender packet format is based on the TWAMP
Session-Sender packet format as defined in Section 4.1.2 of
[RFC5357]. Two new fields (Sender Micro-session ID and Reflector
Micro-session ID) are added to carry the LAG member link identifiers.
For unauthenticated mode, the format is as below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Micro-session ID | Reflector Micro-session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Packet Padding .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Micro Session-Sender Packet Format in Unauthenticated Mode
For authenticated and encrypted mode, the format is as below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| MBZ (12 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Micro-session ID | Reflector Micro-session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Packet Padding .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Micro Session-Sender Packet Format in Authenticated Mode
Except for the Sender Micro-session ID field and the Reflector Micro-
session ID field, all the other fields are the same as defined in
Section 4.1.2 of [RFC5357] and follow the procedure and guidelines
defined therein.
Sender Micro-session ID (2 octets in length): This field is defined
to carry the LAG member link identifier of the Sender side. In
the future, it may be used generically to cover use cases beyond
LAGs. The value of this field MUST be unique within a TWAMP
session at the Session-Sender.
Reflector Micro-session ID (2 octets in length): This field is
defined to carry the LAG member link identifier of the Reflector
side. In the future, it may be used generically to cover use
cases beyond LAGs. The value of this field MUST be unique within
a TWAMP session at the Session-Reflector.
4.2.2. Sender Behavior
The micro TWAMP Session-Sender inherits the behaviors of the TWAMP
Session-Sender as defined in Section 4.1 of [RFC5357]. In addition,
the micro TWAMP Session-Sender MUST send the micro Session-Sender
test packets over the member link with which the session is
associated.
When sending the test packet, the micro TWAMP Session-Sender MUST put
the Sender member link identifier that is associated with the micro
TWAMP session in the Sender Micro-session ID. If the Session-Sender
knows the Reflector member link identifier, the Reflector Micro-
session ID field (see Figures 2 and 3) MUST be set. Otherwise, the
Reflector Micro-session ID field MUST be zero.
A test packet with a Sender member link identifier is sent to the
Session-Reflector and then is reflected with the same Sender member
link identifier. So the Session-Sender can use the Sender member
link identifier to check whether a reflected test packet is received
from the member link associated with the correct micro TWAMP session.
The Reflector member link identifier carried in the Reflector Micro-
session ID field is used by the Session-Reflector to check whether a
test packet is received from the member link associated with the
correct micro TWAMP session. It means that the Session-Sender has to
learn the Reflector member link identifier. Once the Session-Sender
knows the Reflector member link identifier, it MUST put the
identifier in the Reflector Micro-session ID field (see Figures 2 or
3) of the test packets that will be sent to the Session-Reflector.
The Reflector member link identifier can be obtained from
preconfiguration or learned from the data plane (e.g., the reflected
test packet). This document does not specify the way to obtain the
Reflector member link identifier.
When receiving a reflected test packet, the micro TWAMP Session-
Sender MUST use the receiving member link to correlate the reflected
test packet to a micro TWAMP session. If there is no such session,
the reflected test packet MUST be discarded. If a matched session
exists, the micro Session-Sender MUST use the Sender Micro-session ID
to validate whether the reflected test packet is correctly received
from the expected member link. If the validation fails, the test
packet MUST be discarded. The micro Session-Sender MUST use the
Reflector Micro-session ID to validate the Reflector's behavior. If
the validation fails, the test packet MUST be discarded.
4.2.3. Reflector Packet Format and Content
The micro TWAMP Session-Reflector packet format is based on the TWAMP
Session-Reflector packet format as defined in Section 4.2.1 of
[RFC5357]. Two new fields (Sender and Reflector Micro-session ID)
are added to carry the LAG member link identifiers.
For unauthenticated mode, the format is as below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Error Estimate | Sender Micro-session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender TTL | MBZ | Reflector Micro-session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Packet Padding .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Micro Session-Reflector Packet Format in
Unauthenticated Mode
For authenticated and encrypted mode, the format is as below:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Micro-session ID | Reflector Micro-session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Error Estimate | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
| MBZ (6 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender TTL | |
+-+-+-+-+-+-+-+-+ +
| |
| |
| MBZ (15 octets) |
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
| HMAC (16 octets) |
| |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Packet Padding .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Micro Session-Reflector Packet Format in Authenticated Mode
Except for the Sender Micro-session ID field and the Reflector Micro-
session ID field, all the other fields are the same as defined in
Section 4.2.1 of [RFC5357] and follow the same procedure and
guidelines defined therein.
Sender Micro-session ID (2 octets in length): This field is defined
to carry the LAG member link identifier of the Sender side. In
the future, it may be used generically to cover use cases beyond
LAGs. The value of this field MUST be unique within a TWAMP
session at the Session-Sender.
Reflector Micro-session ID (2 octets in length): This field is
defined to carry the LAG member link identifier of the Reflector
side. In the future, it may be used generically to cover use
cases beyond LAGs. The value of this field MUST be unique within
a TWAMP session at the Session-Reflector.
4.2.4. Reflector Behavior
The micro TWAMP Session-Reflector inherits the behaviors of a TWAMP
Session-Reflector as defined in Section 4.2 of [RFC5357].
In addition, when receiving a test packet, the micro TWAMP Session-
Reflector MUST use the receiving member link to correlate the test
packet to a micro TWAMP session. If there is no such a session, the
test packet MUST be discarded. If the Reflector Micro-session ID is
not zero, the Reflector MUST use the Reflector Micro-session ID to
validate whether it associates with the receiving member link. If
the Reflector Micro-session ID is zero, it will not be verified. If
the validation fails, the test packet MUST be discarded.
When sending a response to the received test packet, the micro TWAMP
Session-Reflector MUST copy the Sender member link identifier from
the received test packet and put it in the Sender Micro-session ID
field of the reflected test packet (see Figures 4 and 5). In
addition, the micro TWAMP Session-Reflector MUST fill the Reflector
Micro-session ID field (see Figures 4 and 5) of the reflected test
packet with the member link identifier that is associated with the
micro TWAMP session.
5. Applicability
To set up the micro OWAMP sessions, the Control-Client sends the
Request-OW-Micro-Sessions command to the OWAMP Server. The OWAMP
Server accepts the request and builds a set of micro sessions for all
the member links of the LAG.
For micro TWAMP sessions, a similar set up procedure is used. Then,
the micro TWAMP Session-Sender sends micro Session-Sender packets
with the Sender Micro-session ID and the Reflector Micro-session ID.
If the Reflector Micro-session ID field is set, the micro Session-
Reflector checks whether a test packet is received from the member
link associated with the correct micro TWAMP session. When
reflecting, the micro TWAMP Session-Reflector copies the Sender
Micro-session ID from the received micro Session-Sender packet to the
micro Session-Reflector packet; then, it sets the Reflector Micro-
session ID field with the member link identifier that is associated
with the micro TWAMP session. When receiving the micro TWAMP
Session-Reflector packet, the micro Session-Sender uses the Sender
Micro-session ID to check whether the packet is received from the
member link associated with the correct micro TWAMP session. The
micro Session-Sender also uses the Reflector Micro-session ID to
validate the Reflector's behavior.
6. IANA Considerations
6.1. Micro OWAMP-Control Command
IANA has allocated the following command type from the "OWAMP-Control
Command Numbers" registry.
+=======+===========================+===============+
| Value | Description | Reference |
+=======+===========================+===============+
| 5 | Request-OW-Micro-Sessions | This document |
+-------+---------------------------+---------------+
Table 1: Request-OW-Micro-Sessions Command Number
6.2. Micro TWAMP-Control Command
IANA has allocated the following command type from the "TWAMP-Control
Command Numbers" registry.
+=======+===========================+===============+
| Value | Description | Reference |
+=======+===========================+===============+
| 11 | Request-TW-Micro-Sessions | This document |
+-------+---------------------------+---------------+
Table 2: Request-TW-Micro-Sessions Command Number
7. Security Considerations
This document does not introduce additional security requirements and
mechanisms other than those described in [RFC4656] and [RFC5357].
8. References
8.1. 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>.
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M.
Zekauskas, "A One-way Active Measurement Protocol
(OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006,
<https://www.rfc-editor.org/info/rfc4656>.
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J.
Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)",
RFC 5357, DOI 10.17487/RFC5357, October 2008,
<https://www.rfc-editor.org/info/rfc5357>.
[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>.
[RFC8668] Ginsberg, L., Ed., Bashandy, A., Filsfils, C., Nanduri,
M., and E. Aries, "Advertising Layer 2 Bundle Member Link
Attributes in IS-IS", RFC 8668, DOI 10.17487/RFC8668,
December 2019, <https://www.rfc-editor.org/info/rfc8668>.
8.2. Informative References
[IEEE802.1AX]
IEEE, "IEEE Standard for Local and Metropolitan Area
Networks -- Link Aggregation", IEEE Std 802.1AX-2020,
DOI 10.1109/IEEESTD.2020.9105034, May 2020,
<https://ieeexplore.ieee.org/document/9105034>.
[RFC7799] Morton, A., "Active and Passive Metrics and Methods (with
Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
May 2016, <https://www.rfc-editor.org/info/rfc7799>.
Acknowledgements
The authors would like to thank Fang Xin, Henrik Nydell, Mach Chen,
Min Xiao, Jeff Tantsura, Marcus Ihlar, and Richard Foote for the
valuable comments to this work.
Authors' Addresses
Zhenqiang Li
China Mobile
No. 29 Finance Avenue
Xicheng District
Beijing
China
Email: li_zhenqiang@hotmail.com
Tianran Zhou
Huawei
China
Email: zhoutianran@huawei.com
Jun Guo
ZTE Corp.
China
Email: guo.jun2@zte.com.cn
Greg Mirsky
Ericsson
United States of America
Email: gregimirsky@gmail.com
Rakesh Gandhi
Cisco Systems, Inc.
Canada
Email: rgandhi@cisco.com