Fast Notification for tunnel-based lossless RDMA transmission in WAN
draft-hzh-fantel-wan-tunnel-02
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| Authors | Zehua Hu , Yongqing Zhu , Jiayuan Hu , Tanxin Pi | ||
| Last updated | 2026-03-01 (Latest revision 2025-10-17) | ||
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draft-hzh-fantel-wan-tunnel-02
RTGWG Z. Hu
Internet-Draft Y. Zhu
Intended status: Standards Track J. Hu
Expires: 2 September 2026 T. Pi
China Telecom
1 March 2026
Fast Notification for tunnel-based lossless RDMA transmission in WAN
draft-hzh-fantel-wan-tunnel-02
Abstract
With the rapid development of Large Language Models (LLMs), many
emerging AI services require lossless transmission of RDMA traffic
over tunnels in Wide Area Network(WAN). Existing network mechanisms
were not designed for the responsiveness and scale required by these
dynamic services. WAN should support the real-time, lightweight
network notification to enhance the responsiveness for traffic
engineering, congestion mitigation, and failure protection.
This document analyzes typical scenarios where RDMA traffic need to
be tunneled across WAN, and proposes fast network notification
solutions based on ICMPv6 or UDP.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 2 September 2026.
Copyright Notice
Copyright (c) 2026 IETF Trust and the persons identified as the
document authors. All rights reserved.
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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 publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 4
3. Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Scenario 1: distributed model training across DCs . . . . 4
3.2. Scenario 2: distributed model inference between on-premise
and third-party DC . . . . . . . . . . . . . . . . . . . 4
3.3. Scenario abstraction . . . . . . . . . . . . . . . . . . 4
4. Process analyze . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. Failure protection . . . . . . . . . . . . . . . . . . . 6
4.2. Congestion control . . . . . . . . . . . . . . . . . . . 7
4.3. Load balancing for network state changes . . . . . . . . 8
5. Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1. ICMPv6-based solution . . . . . . . . . . . . . . . . . . 9
5.2. UDP-based solution . . . . . . . . . . . . . . . . . . . 11
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References . . . . . . . . . . . . . . . . . . 13
9.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
For modern AI services such as distributed LLMs training or
inference, WAN needs to support the tunneling of RDMA traffic between
data centers (DCs). RDMA is a widely used technology in high-
performance computing and AI clusters, achieving low latency, reduced
CPU overhead, and high network throughput. Currently, mainstream
RDMA protocols (e.g., IB, RoCE) operate over best-effort forwarding,
where a small number of packet losses can result in a dramatic
reduction in the effective throughput. Therefore, WAN requires the
FAst Notification for Traffic Engineering and Load balancing (FANTEL)
to ensure reliable and congestion-free data transfer.
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[I-D.geng-fantel-fantel-gap-analysis] points existing TE mechanisms
face limitations in responsiveness, coverage, and operational
overhead, especially in high-speed, large-scale environments.
ECN[RFC3168] is a widely deployed congestion control mechanism, which
enables a forwarding element to notify the sender for congestion
control without having to drop packets. But it still relies on end-
to-end signaling, making real-time feedback challenging in long-
distance WAN. BFD[RFC5880] is designed for rapid fault detection by
sending frequent control packets between peers, but higher probe
frequency increases CPU and bandwidth usage, make it struggles to
balance detection speed with system overhead.
[I-D.ietf-rtgwg-net-notif-ps] is an IETF Problem Statement for
FANTEL, based on the analysis of gaps in current network mechanisms
and the operational requirements of modern applications (e.g., AI/ML
training), formally defines the scope and core requirements for fast
network notifications. Moreover, it futher specifies what
information such notifications carry, who the intended recipients
are, how they should be delivered, and what kinds of timely actions
they may enable.
To enable lossless data transmission, some drafts are proposed to
support FANTEL. [I-D.wh-rtgwg-adaptive-routing-arn] proposes a
proactive notification mechanism ARN for adaptive routing, and
describes the information carried in ARN to notify remote nodes for
re-routing. [I-D.liu-rtgwg-adaptive-routing-notification] describes
the mechanisms of delivering ARN message.
This document specifies the FANTEL mechanism for scenarios where
service traffic is carried over tunnels in WAN. It first introduces
the typical scenarios, then specifies the process of fast
notification to achieve key TE areas such as congestion control, load
balancing, and failure protection, and finally defines the protocol
implementation.
2. Conventions
2.1. Abbreviations
CNP: Congestion Notification Packet
ECN: Explicit Congestion Notification
FANTEL: FAst Notification for Traffic Engineering and Load balancing
PFC: Priority-based Flow Control
RoCEv2: RDMA over Converged Ethernet version 2
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WAN: Wide Area Network
2.2. 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.
3. Scenarios
3.1. Scenario 1: distributed model training across DCs
The growth of computing power of a single DC is limited by space and
power supply, making it difficult to meet the fast-growing computing
resources demands of LLMs training. Therefore, distributed model
training across multiple DCs provides a more efficient and cost-
effective solution to aggregate computing resources. In this
scenario, TB-scale training parameters need to be rapidly
synchronized over WAN.
3.2. Scenario 2: distributed model inference between on-premise and
third-party DC
Some customers deploy LLMs by building on-premises AI facilities, but
as inference concurrency increases, scaling out these facilities
requires significant investment. To address this, distributed model
inference between customer on-premise and third-party DC provides a
more agile and cost-effective solution. In this scenario, data such
as the KV cache and model parameters need to be rapidly synchronized
over WAN.
3.3. Scenario abstraction
In the above scenarios, a large volume of data between DCs need to be
synchronized using RDMA protocol. RDMA traffic generated by LLM
training or inference is highly concurrent, bursty, and extremely
latency-sensitive. Therefore, operators typically encapsulate it in
tunnels over the WAN to enable flexible steering and end-to-end
service isolation. In these scenarios, the framework for RDMA
traffic transmission over WAN tunnels is as follows:
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+--------------------------------------------------+
| DC1 |
| |
| +-----------+ +-----------+ +-----------+ |
| |AI server 1| |AI server 2| ... |AI server n| |
| +-----------+ +-----------+ +-----------+ |
+------------------------+-------------------------+
|
+------------------------+-------------------------+
| WAN +-----+----+ |
| +------+ingress PE+------+ |
| | +----------+ | |
| | | |
| +--+---+ +--+---+ |
| | R1 + + R2 | |
| +--+---+\ /+--+---+ |
| | \ / | |
| | \+---------+/ | |
| | + R5 + | |
| | /+---------+\ | |
| | / \ | |
| +--+---+/ \+--+---+ |
| | R3 + + R4 | |
| +--+---+ +--+---+ |
| | | |
| | +---------+ | |
| +-------+egress PE+------+ |
| +----+----+ |
+------------------------+-------------------------+
|
+------------------------+-------------------------+
| +-----------+ +-----------+ +-----------+ |
| |AI server 1| |AI server 2| ... |AI server m| |
| +-----------+ +-----------+ +-----------+ |
| |
| DC2 |
+--------------------------------------------------+
Figure 1: Network diagram
* The AI servers in DC1 sends RDMA traffic to WAN's ingress PE.
* At the WAN's ingress PE, the RDMA traffic is encapsulated
according to the tunnel protocol and forwarded across WAN to
egress PE.
* The WAN's P node(R1-R5) transits the payload from ingress PE to
egress PE via tunnels.
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* At the WAN's egress PE, the payload are decapsulated to RDMA
packets and transmitted to the AI servers in DC2.
4. Process analyze
Tunneling technologies include various protocols, such as GRE, VXLAN,
MPLS, and SRv6. Moreover, AI workloads are highly sensitive to
packet loss, latency and throughput. Network failures, congestion or
underutilization can all lead to significant waste of compute
resources. When transmittig RDMA traffic over tunnels, WAN should
support FANTEL capability to realize rapid response to network
conditions. Specifically, WAN devices should support fast
notification mechanism to imporve three key TE scenarios: failure
protection, flow control, and load balancing.
4.1. Failure protection
For large-scale and dynamic networks, protection mechanisms need to
ensure service continuity in case of failures. According to
[I-D.geng-fantel-fantel-gap-analysis], existing failure handling
methods, such as BFD and FRR, lack flexibility and responsiveness in
complex typologies. Therefore, WAN should support fast notification
for failures, allowing near-instantaneous and dynamic protection
responses, minimizing failure impact.
Upon network failure, the ingress PE should immediately adapt its
forwarding policy to steer traffic away from faulty links or nodes.
Therefore, the fast-notification-based failure protection process is
as follows:
notification
+--------------+
| |
| +---+--+ +------+
| | R1 +--x-+ R2 |
| /+------+ ^ +------+\
| / | \
v / failure \
+----------+ / \ +---------+
| |/ \| |
|ingress PE|\ /|egress PE|
| | \ / | |
+----------+ \ / +---------+
\ +------+ +------+ /
\| R3 +----+ R4 |/
+------+ +------+
Figure 2: Failure protection procession
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* When a P node detects a local link/node failure, it collects
failure information about the affected link or flow.
* The P node sends notification to ingress PE with failure
information (In addition to the identity of the failed link or
node, the notification must also include information about the
affected traffic).
* Ingress PE receives the notification and reroutes the traffic
based on its content to exclude the failed link or node: *If
backup path is available, ingress PE should switch the service
traffic to the backup path. *If multiple feasible paths exist,
ingress PE should updates its load-balancing policy to utilize all
available paths. *If no feasible path is available, ingress PE
should send a corresponding notification to the sender and
controller.
4.2. Congestion control
RDMA traffic is bursty and highly sensitive to packet loss, and WAN
require proactive congestion control mechanisms. [RFC6040] redefines
how the explicit congestion notification (ECN) field of the IP header
should be constructed on entry to and exit from any IP-in-IP tunnel,
in order to achieve ECN-based congestion control across WANs between
DCs. However, [I-D.geng-fantel-fantel-gap-analysis] analysis that
ECN/TCP methods still relies on end-to-end signaling and lacks
precise real-time feedback.
Currently, PFC is widely used in data centers to prevent data loss
due to congestion. PFC uses a step-by-step back-pressure mechanism
to control the upstream to stop or continue transmitting traffic.
PFC achieves link-layer priority-based traffic control, but still
faces problems such as queue head blocking and deadlock due to coarse
control granularity.
When network congestion occurs, the ingress PE should immediately
adapt its forwarding policy to reduce the traffic sent to congested
nodes. Meanwhile, the upstream nodes to the congested node should
reduce the transmission rate of corresponding traffic to minimize the
likelihood of packet loss. Therefore, the fast-notification-based
congestion control process is as follows:
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notification
+---------------------------+
| |
| +------+ +-+--+-+
| | R1 +----+ R2 |
| /+------+ +------+\
| / x<---congestion
v / \
+----------+ / \ +---------+
| |/ \| |
|ingress PE|\ /|egress PE|
| | \ / | |
+----------+ \ / +---------+
\ +------+ +------+ /
\| R3 +----+ R4 |/
+------+ +------+
Figure 3: Congestion control procession
* when a P node detects congestion, it collects congestion
information about the congested link or flow.
* The P node sends notification to ingress PE and upstream with
congestion information.
* The upstream P node receives the notification and reduce the
transmission rate of corresponding traffic.
* Ingress PE receives the notification and reroutes the traffic
based on its content to exclude the congestion link: *If backup
path is available, ingress PE should switch the service traffic to
the backup path. *If multiple feasible paths exist, ingress PE
should updates its load-balancing policy to utilize all available
paths. *If no feasible path is available, ingress PE should
reduce the transmission rate of corresponding traffic, and send
notification to sender and controller.
4.3. Load balancing for network state changes
Devices and links in WAN often carry multiple services
simultaneously. In addition to failure and congestion, dynamic load
balancing based on network state changes can effectively improve
network resource utilization.
When significant changes occur in the network state, the ingress PE
should dynamically adjust its forwarding strategy to maximize network
resource utilization. Therefore, the fast-notification-based load
balancing process is as follows:
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notification
+--------------+
| |
| +---+--+ +------+
| | R1 +----+ R2 |
| /+------+ ^ +------+\
| / | \
v / link utilization \
+----------+ / change \ +---------+
| |/ \| |
|ingress PE|\ /| gress PE|
| | \ node load change/ | |
+----------+ \ | / +---------+
^ \ v /
| \+------+ +------+/
| | R3 +----+ R4 |
| +------+ +---+--+
| |
+--------------------------+
notification
Figure 4: Load balancing for network state changes
* When a node detects the network state change, it collects the
network state change information, such as link utilization, queue
buildup.
* The node sends fast notification to the ingress PE with
information about the network state change.
* Ingress PE receives the fast notification and updates its load-
balancing policy to maximize the utilization of network resources.
5. Solutions
Based on the framework analysis of fast notification in key TE areas,
a unified protocol implementation for fast notification should be
established, with explicit forwarding procedures to realize tunnel-
based lossless transmission of RDMA packets in WAN.
5.1. ICMPv6-based solution
The source quench mechanism has been deprecated in ICMPv6 because
TCP's built-in congestion avoidance algorithms are more efficient,
and source quench may interfere with their normal operation.
However, when transmitting RDMA data over WAN tunnels, the source
quench notification is confined within the WAN domain (this message
is used by WAN devices such as Ingress PE or transit node for traffic
engineering) and does not affect transport layer congestion control.
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This document specifies a new ICMPv6 message to realize rapid
notification in key traffic engineering areas including failure
protection, congestion control, and load balancing. The message
format is defined as follows:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TYPE | CODE | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Tunnel Info |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: new ICMPv6 message for fast notification
TYPE:8-bit identifier for the purposes of notification. This
document defines the following five TYPEs:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TYPE | description |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TYPE1(TBA) | notification for failure |
| TYPE2(TBA) | notification for failure recovery |
| TYPE3(TBA) | notification for congestion |
| TYPE4(TBA) | notification for congestion elimination |
| TYPE5(TBA) | notification for load balancing |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Table 1: description for TYPEs
CODE: This field is an 8-bit bitmap (bit 0 - 7), indicating which
tunneling mechanism(s) are encoded in the Tunnel Info field. * If
bit 0 is set to 1, the packet is forwarded based on IPv4 or IPv6
destination address lookup. This applies to IP-based tunnels such as
GRE and IPsec. In this case, the Tunnel Info field contains the
destination IPv4 or IPv6 address. * If bit 1 is set to 1, the packet
is forwarded according to an SRv6 Policy. In this case, the Tunnel
Info field contains a Segment Routing Header (SRH) as defined in RFC
8754. * If bit 2 is set to 1, the packet is forwarded using MPLS
switching. In this case, the Tunnel Info field contains an MPLS shim
header as defined in RFC 3032. Bits 3 through 7 are reserved for
future use and MUST be set to 0 by the sender and ignored by the
receiver.
Checksum: Used for error-checking the packet.
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Tunnel Info: This field carries tunnel-specific information (e.g.,
destination address, SRH, or MPLS shim header) required by the
recipient node to identify and divert traffic away from the affected
path. Upon receiving a message containing this field, the recipient
node SHALL cease forwarding traffic along the specified path.
options: A TLV-encoded optional field that conveys additional
telemetry, traffic, or network state information to support fine-
grained flow control. The TLV format is shown in Figure 6. It MAY
include the following categories: * Event Location: Identifies where
the triggering event occurred — e.g., the affected link or node. *
Flow Information: Describes the traffic flow impacted by the event —
e.g., its identity (such as a Flow ID) or transport 5-tuple. * State
Metrics: Quantifiable network measurements — e.g., link utilization,
queue length, one-way delay, or packet loss rate. The format of TLVs
conveying link identifiers, node identifiers, and network metrics
SHALL follow the corresponding definitions in BGP-LS [RFC7752] and
the BGP-LS extensions [RFC8571].
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TYPE | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Value (variable) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: TLV Format
5.2. UDP-based solution
This document specifies a new UDP message to realize rapid
notification in key traffic engineering areas including failure
protection, congestion control, and load balancing. The message
format is defined as follows:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| UDP source port | UDP destination port(TBD) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| UDP length | UDP Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Type | Code | Rvsd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| tunnel info |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: new UDP message for fast notification
Version: This field indicates the version number. The default value
is 0.
The definitions of the TYPE, CODE, tunnel info, and Options fields
are the same as those in Section 5.1.
Rvsd:Reserved
6. Security Considerations
This document specifies Fast Notification (FANTEL) mechanisms for
tunnel-based lossless RDMA transmission in WAN, using ICMPv6 and UDP
as transport protocols. While these protocols are widely deployed
and well-understood, extending them with new notification semantics
introduces potential security considerations that must be addressed.
Implementations MUST enforce the rate limiting behavior specified in
RFC 4443 [RFC4443] §2.4 for all ICMPv6 messages carrying FANTEL
information.
The TLV parser MUST validate that the sum of all TLV Length fields
does not exceed the total ICMPv6 payload length. Any packet failing
this check MUST be silently discarded.
All FANTEL notifications MUST be sent from a control-plane interface
of the originating node (e.g., a loopback interface configured for
management), and MUST NOT originate from data-plane forwarding
interfaces (e.g., physical ports carrying customer traffic). This
ensures that FANTEL traffic cannot be injected by compromised
customer devices.
TBD
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7. IANA Considerations
TBD
8. Acknowledgments
TBD
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>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
9.2. Informative References
[RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
of Explicit Congestion Notification (ECN) to IP",
RFC 3168, DOI 10.17487/RFC3168, September 2001,
<https://www.rfc-editor.org/info/rfc3168>.
[RFC6040] Briscoe, B., "Tunnelling of Explicit Congestion
Notification", RFC 6040, DOI 10.17487/RFC6040, November
2010, <https://www.rfc-editor.org/info/rfc6040>.
[RFC7514] Luckie, M., "Really Explicit Congestion Notification
(RECN)", RFC 7514, DOI 10.17487/RFC7514, April 2015,
<https://www.rfc-editor.org/info/rfc7514>.
[RFC4443] Gupta, Mukesh., "Internet Control Message Protocol
(ICMPv6) for the Internet Protocol Version 6 (IPv6)
Specification", RFC 4443, DOI 10.17487/RFC4443, March
2006, <https://www.rfc-editor.org/info/rfc4443>.
[RFC5880] Katz, Dave., "Bidirectional Forwarding Detection (BFD)",
RFC 5880, DOI 10.17487/RFC5880, January 2010,
<https://www.rfc-editor.org/info/rfc5880>.
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[I-D.wh-rtgwg-adaptive-routing-arn]
Wang, H., Huang, H., Geng, X., Xu, X., and Y. Xia,
"Adaptive Routing Notification", Work in Progress,
Internet-Draft, draft-wh-rtgwg-adaptive-routing-arn-03, 13
September 2024, <https://datatracker.ietf.org/doc/html/
draft-wh-rtgwg-adaptive-routing-arn-03>.
[I-D.liu-rtgwg-adaptive-routing-notification]
Liu, Y., lihesong, and W. Duan, "Adaptive Routing
Notification for Load-balancing", Work in Progress,
Internet-Draft, draft-liu-rtgwg-adaptive-routing-
notification-02, 12 June 2025,
<https://datatracker.ietf.org/doc/html/draft-liu-rtgwg-
adaptive-routing-notification-02>.
[I-D.xiao-rtgwg-rocev2-fast-cnp]
Min, X. and lihesong, "Fast Congestion Notification Packet
(CNP) in RoCEv2 Networks", Work in Progress, Internet-
Draft, draft-xiao-rtgwg-rocev2-fast-cnp-03, 9 June 2025,
<https://datatracker.ietf.org/doc/html/draft-xiao-rtgwg-
rocev2-fast-cnp-03>.
[I-D.geng-fantel-fantel-gap-analysis]
Geng, X., Huo, P., Cheng, W., Li, D., Zhu, Y., and H.
Zhengxin, "Gap Analysis of Fast Notification for Traffic
Engineering and Load Balancing", Work in Progress,
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7 July 2025, <https://datatracker.ietf.org/doc/html/draft-
geng-fantel-fantel-gap-analysis-01>.
[I-D.ietf-rtgwg-net-notif-ps]
Dong, J., McBride, M., Clad, F., Zhang, Z. J., Zhu, Y.,
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Authors' Addresses
Zehua Hu
China Telecom
Guangzhou
China
Email: huzh2@chinatelecom.cn
Hu, et al. Expires 2 September 2026 [Page 14]
Internet-Draft Fast Notification for tunnel-based lossl March 2026
Yongqing Zhu
China Telecom
Guangzhou
China
Email: zhuyq8@chinatelecom.cn
Jiayuan Hu
China Telecom
Guangzhou
China
Email: hujy5@chinatelecom.cn
Tanxin Pi
China Telecom
Guangzhou
China
Email: pitx1@chinatelecom.cn
Hu, et al. Expires 2 September 2026 [Page 15]