Network Working Group
Internet Engineering Task Force (IETF) A. Huang-Feng
Internet-Draft
Request for Comments: 9984 P. Francois
Intended status:
Category: Standards Track INSA-Lyon
Expires: 19 June 2026
ISSN: 2070-1721 K. Watsen
Watsen Networks
16 December 2025
May 2026
YANG Groupings for UDP Clients and UDP Servers
draft-ietf-netconf-udp-client-server-10
Abstract
This document defines two YANG 1.1 modules with reusable groupings
for managing UDP clients and UDP servers.
Notes to the RFC editor
This note is to be removed before publishing as an RFC.
Please replace "RFC XXXX" with the assigned RFC number prior to
publication. Note that there are also several occurrences of "RFC
XXXX" in the YANG modules.
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 an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum 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 six months this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained 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 19 June 2026.
https://www.rfc-editor.org/info/rfc9984.
Copyright Notice
Copyright (c) 2025 2026 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)
(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 extracted from this document must
include Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 2
1.2. Adherence to the NMDA . . . . . . . . . . . . . . . . . . 3
1.3. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3
2. The "ietf-udp-client" Module . . . . . . . . . . . . . . . . 3
2.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 3
2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 4
2.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 5
3. The "ietf-udp-server" Module . . . . . . . . . . . . . . . . 7
3.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 7
3.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 8
3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 9
4. Security Considerations . . . . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
5.1. URI . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 The "IETF XML Registry"
5.2. YANG The "YANG Module Name . . . . . . . . . . . . . . . . . . . . 12 Names" Registry
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
7.1.
6.1. Normative References . . . . . . . . . . . . . . . . . . 12
7.2.
6.2. Informative References . . . . . . . . . . . . . . . . . 13
Acknowledgements
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
This document defines two YANG 1.1 [RFC7950] modules with reusable
groupings for managing UDP clients and UDP servers [RFC768]. These
modules may be used directly (e.g., define a specific UDP client or
UDP server) or in conjunction with the configuration defined for
higher level
higher-level protocols that depend on UDP.
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.
1.2. Adherence to the NMDA
This document is compliant with the Network Management Datastore
Architecture (NMDA) [RFC8342]. It does not define any protocol protocol-
accessible nodes that are "config false".
1.3. Conventions
Various examples in this document use the XML [W3C.REC-xml-20081126]
encoding. Other encodings, such as JSON [RFC8259], could
alternatively be used.
2. The "ietf-udp-client" Module
This section defines a YANG 1.1 module called "ietf-udp-client".
This YANG module defines the "udp-client" grouping for providing UDP
clients with remote server information.
Section 2.1 provides the overview of the YANG module. An example of
usage is illustrated in Section 2.2, while 2.2. Section 2.3 defines the YANG
module itself.
2.1. Data Model Overview
This section provides an overview of the features and the grouping
defined in the "ietf-udp-client" YANG module.
2.1.1. Features
The "ietf-udp-client" module defines the following "feature"
statement:
Features:
+-- local-binding
The diagram above uses syntax that is similar to the syntax used in
[RFC8340]; but the syntax from the diagram is not defined in
[RFC8340].
This feature indicates that the client supports configuring local
bindings (i.e., the local address and local port number) for UDP
clients.
2.1.2. The "udp-client" Grouping
The following tree diagram [RFC8340] illustrates the tree structure
of the "udp-client" grouping:
module: ietf-udp-client
grouping udp-client:
+-- remote-address inet:host
+-- remote-port? inet:port-number
+-- local-address? inet:ip-address {local-binding}?
+-- local-port? inet:port-number {local-binding}?
The description of these parameters is provided below:
* The "remote-address", which is mandatory, may be configured as an
IPv4 address, an IPv6 address, or a hostname. The resolved
address should be compatible with the local address family, if
also provided.
* The "remote-port" is defined with neither a "default" nor a
"mandatory" statement. YANG modules using this grouping SHOULD
refine the grouping with a "default" statement, statement when the port
number is well-known (e.g., a port number allocated by IANA), IANA) or
with a "mandatory" statement, statement if a port number needs to always be
configured. This MAY be ignored when the port number is neither
well-known nor mandatory to configure, such as might be the case
when this grouping is used by another grouping.
* The "local-address", which is enabled by the "local-binding"
feature, may be configured as an IPv4 address, an IPv6 address, or
a wildcard value. In normal operation, the local and configured
remote addresses SHOULD be from the same address family.
Differences between address families may occur in abnormal or
error conditions and conditions; therefore, they are therefore allowed to be reported.
* The "local-port", which depends on the "local-binding" feature, is
not mandatory. Its default value is "0", indicating that the
operating system can select an arbitrary port number.
2.2. Example Usage
This section presents an example of usage of the "udp-client"
grouping.
<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<udp-client xmlns="urn:ietf:params:xml:ns:yang:ietf-udp-client">
<remote-address>www.example.com</remote-address>
<remote-port>10000</remote-port>
<local-address>192.0.2.2</local-address>
<local-port>12345</local-port>
</udp-client>
2.3. YANG Module
This module imports types defined in [I-D.ietf-netmod-rfc6991-bis]. [RFC9911].
<CODE BEGINS> file "ietf-udp-client@2025-12-16.yang" "ietf-udp-client@2026-05-13.yang"
module ietf-udp-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-udp-client";
prefix udpc;
import ietf-inet-types {
prefix inet;
reference
"RFC 9911: Common YANG Data Types";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/group/netconf/>
WG List: <mailto:netconf@ietf.org>
Authors: Alex Huang Feng
<mailto:alex.huang-feng@insa-lyon.fr>
Pierre Francois
<mailto:pierre.francois@insa-lyon.fr>";
description
"Defines a generic grouping for UDP-based client applications.
Copyright (c) 2025 2026 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry group
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; 9984; see
the RFC itself for full legal notices.
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 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
revision 2025-12-16 2026-05-13 {
description
"Initial revision";
reference
"RFC XXXX: 9984: YANG Groupings for UDP Clients and UDP Servers";
}
feature local-binding {
description
"Indicates that the UDP client supports configuring local
bindings (i.e., the local address and local port number)
for UDP clients.";
}
grouping udp-client {
description
"A reusable grouping for UDP clients.
Note that this grouping uses fairly typical descendant
node names such that a stack of 'uses' statements will
have name conflicts. It is intended that the consuming
data model will resolve the issue (e.g., by wrapping
the 'uses' statement in a container called
'udp-client-parameters'). This model module purposely does
not do this itself so as to provide maximum flexibility
to consuming models.";
leaf remote-address {
type inet:host;
mandatory true;
description
"The IP address or hostname of the remote UDP server.";
}
leaf remote-port {
type inet:port-number;
description
"The port number of the remote UDP server.";
}
leaf local-address {
if-feature "local-binding";
type inet:ip-address;
description
"The local IP address to bind to when sending UDP
datagrams to the remote server. INADDR_ANY ('0.0.0.0') or
INADDR6_ANY ('0:0:0:0:0:0:0:0' a.k.a. '::') may be used
so that the client can bind to any IPv4 or IPv6 address.
In normal operation, the local and configured
remote addresses SHOULD be from the same address family.
Differences between address families may occur in
abnormal or error conditions and conditions; therefore, they are therefore allowed to
be reported.";
}
leaf local-port {
if-feature "local-binding";
type inet:port-number;
default "0";
description
"The local port number to bind to when sending UDP
datagrams to the remote server. The port number '0',
which is the default value, indicates that any available
local port number may be used.";
}
}
}
<CODE ENDS>
3. The "ietf-udp-server" Module
This section defines a YANG 1.1 module called "ietf-udp-server".
This YANG module defines the "udp-server" grouping for managing UDP
servers.
Section 3.1 provides an overview of the "ietf-udp-server" YANG
module. An example of usage is illustrated in Section 3.2 while 3.2.
Section 3.3 defines the YANG module itself.
3.1. Data Model Overview
This section provides an overview of the grouping defined in the
"ietf-udp-server" module.
3.1.1. The "udp-server" Grouping
The following tree diagram [RFC8340] illustrates the tree structure
of "udp-server" grouping:
module: ietf-udp-server
grouping udp-server:
+-- local-bind* [local-address]
+-- local-address inet:ip-address
+-- local-port? inet:port-number
The description of these parameters is provided below:
* The "local-address", which is mandatory, may be configured as an
IPv4 address, an IPv6 address, or a wildcard value.
* The "local-port" is defined with neither a "default" nor a
"mandatory" statement. YANG modules using this grouping SHOULD
refine the grouping with a "default" statement, statement when the port
number is well-known (e.g., a port number allocated by IANA), IANA) or
with a "mandatory" statement, statement if a port number needs to always be
configured. This MAY be ignored when the port number is neither
well-known nor mandatory to configure, such as might be the case
when this grouping is used by another grouping.
3.2. Example Usage
This section presents two examples of usage of the "udp-server"
grouping.
This
The following shows an example of a server configured for listening
to an IPv4 address:
<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<udp-server xmlns="urn:ietf:params:xml:ns:yang:ietf-udp-server">
<local-bind>
<local-address>192.0.2.2</local-address>
<local-port>49152</local-port>
</local-bind>
</udp-server>
This
The following shows an example of a server configured to listen for listening
to an IPv4 and IPv6 together:
<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<udp-server xmlns="urn:ietf:params:xml:ns:yang:ietf-udp-server">
<local-bind>
<local-address>192.0.2.2</local-address>
<local-port>49152</local-port>
</local-bind>
<local-bind>
<local-address>2001:db8::0</local-address>
<local-port>49153</local-port>
</local-bind>
</udp-server>
3.3. YANG Module
The "ietf-udp-server"
This module imports types defined in
[I-D.ietf-netmod-rfc6991-bis]. [RFC9911].
<CODE BEGINS> file "ietf-udp-server@2025-12-16.yang" "ietf-udp-server@2026-05-13.yang"
module ietf-udp-server {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-udp-server";
prefix udps;
import ietf-inet-types {
prefix inet;
reference
"RFC 9911: Common YANG Data Types";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/group/netconf/>
WG List: <mailto:netconf@ietf.org>
Authors: Alex Huang Feng
<mailto:alex.huang-feng@insa-lyon.fr>
Pierre Francois
<mailto:pierre.francois@insa-lyon.fr>";
description
"Defines a generic grouping for UDP-based server applications.
Copyright (c) 2025 2026 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry group
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; 9984; see
the RFC itself for full legal notices.";
revision 2025-12-16 2026-05-13 {
description
"Initial revision";
reference
"RFC XXXX: 9984: YANG Groupings for UDP Clients and UDP Servers";
}
grouping udp-server {
description
"Provides a
"A reusable grouping for managing UDP servers.
Note that this grouping uses fairly typical descendant
node names such that a stack of 'uses' statements will
have name conflicts. It is intended that the consuming
data model will resolve the issue (e.g., by wrapping
the 'uses' statement in a container called
'udp-server-parameters'). This model module purposely does
not do this itself so as to provide maximum flexibility
to consuming models.";
list local-bind {
key "local-address";
min-elements 1;
description
"A list of bind (listen) points for this server
instance. A server instance may have multiple
bind points to support, e.g., the same port number in
different address families or different port numbers
in the same address family.";
leaf local-address {
type inet:ip-address;
mandatory true;
description
"The local IP address to listen on for incoming
UDP datagrams. INADDR_ANY ('0.0.0.0') or
INADDR6_ANY ('0:0:0:0:0:0:0:0' a.k.a. '::') may be used
so that the server can listen to any IPv4 or IPv6
address.";
}
leaf local-port {
type inet:port-number;
description
"The local port number to listen on for incoming UDP
datagrams.";
}
}
}
}
<CODE ENDS>
4. Security Considerations
This section uses the template described in Section 3.7 3.7.1 of
[I-D.ietf-netmod-rfc8407bis].
[RFC9907].
The "ietf-udp-client" and "ietf-udp-server" YANG modules defines define a
data model that is designed to be accessed via YANG-based management
protocols, such as NETCONF Network Configuration Protocol (NETCONF) [RFC6241]
and RESTCONF [RFC8040]. These YANG-based management protocols (1)
have to use a secure transport layer (e.g., SSH [RFC6242], [RFC4252], TLS
[RFC8446], and QUIC [RFC9000]) and (2) have to use mutual
authentication.
The Network Configuration Access Control Model (NACM) [RFC8341]
provides the means to restrict access for particular NETCONF or
RESTCONF users to a preconfigured subset of all available NETCONF or
RESTCONF protocol operations and content.
These YANG modules define a set of identities, types, and groupings.
These nodes are intended to be reused by other YANG modules. The
modules by themselves do not expose any data nodes that are writable,
data nodes that contain read-only state, or RPCs. As such, there are
no additional security issues related to the YANG module modules that need
to be considered.
Modules that use the groupings that are defined in this document
should identify the corresponding security considerations. For
example, reusing some of these groupings will expose privacy-related
information (e.g., 'remote-address', 'remote-port', 'local-address',
or 'local-port').
5. IANA Considerations
This document describes the URIs from IETF the "IETF XML Registry Registry" and the
registration of a two new YANG module names names.
5.1. URI The "IETF XML Registry"
IANA is requested to assign has assigned two new URIs from the IETF "IETF XML Registry Registry"
[RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-udp-client
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-udp-server
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
5.2. YANG The "YANG Module Name
This document also requests Names" Registry
IANA to register has registered the following YANG modules in the YANG "YANG Module Names
Names" registry [RFC6020] within the "YANG Parameters" registry
group:
name:
Name: ietf-udp-client
namespace: urn:ietf:params:xml:ns:yang:ietf-udp-client
prefix: udpc
maintained
Maintained by IANA? N
reference:
Namespace: urn:ietf:params:xml:ns:yang:ietf-udp-client
Prefix: udpc
Reference: RFC XXXX
name: 9984
Name: ietf-udp-server
namespace: urn:ietf:params:xml:ns:yang:ietf-udp-server
prefix: udps
maintained
Maintained by IANA? N
reference:
Namespace: urn:ietf:params:xml:ns:yang:ietf-udp-server
Prefix: udps
Reference: RFC XXXX 9984
6. Acknowledgements
The authors would like to thank Mohamed Boucadair, Ran Chen, Benoit
Claise, Mahesh Jethanandani, Qiufang Ma, Jürgen Schönwälder, Ketan
Talaulikar, Eric Vyncke, Paul Wouters and Qin Wu for their review and
valuable comments.
7. References
7.1.
6.1. Normative References
[I-D.ietf-netmod-rfc6991-bis]
Schönwälder, J., "Common YANG Data Types", Work in
Progress, Internet-Draft, draft-ietf-netmod-rfc6991-bis-
18, 23 June 2025, <https://datatracker.ietf.org/doc/html/
draft-ietf-netmod-rfc6991-bis-18>.
[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>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC768] Postel, J., "User Datagram Protocol", STD 6, RFC 768,
DOI 10.17487/RFC0768, August 1980,
<https://www.rfc-editor.org/info/rfc768>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[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>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
7.2. Informative References
[I-D.ietf-netmod-rfc8407bis]
Bierman, A., Boucadair, M., and Q. Wu, "Guidelines for
Authors and Reviewers of Documents Containing
[RFC9911] Schönwälder, J., Ed., "Common YANG Data
Models", Work in Progress, Internet-Draft, draft-ietf-
netmod-rfc8407bis-28, 5 June Types", RFC 9911,
DOI 10.17487/RFC9911, December 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
rfc8407bis-28>.
<https://www.rfc-editor.org/info/rfc9911>.
6.2. Informative References
[RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
January 2006, <https://www.rfc-editor.org/info/rfc4252>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/info/rfc9000>.
[RFC9907] Bierman, A., Boucadair, M., Ed., and Q. Wu, "Guidelines
for Authors and Reviewers of Documents Containing YANG
Data Models", BCP 216, RFC 9907, DOI 10.17487/RFC9907,
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[W3C.REC-xml-20081126]
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Ed., Maler, E., Ed., and F. Yergeau, Ed., "Extensible
Markup Language (XML) 1.0 (Fifth Edition)", World Wide Web Consortium
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Acknowledgements
The authors would like to thank Mohamed Boucadair, Ran Chen, Benoit
Claise, Mahesh Jethanandani, Qiufang Ma, Jürgen Schönwälder, Ketan
Talaulikar, Éric Vyncke, Paul Wouters, and Qin Wu for their reviews
and valuable comments.
Authors' Addresses
Alex Huang Feng
INSA-Lyon
Lyon
France
Email: alex.huang-feng@insa-lyon.fr
Pierre Francois
INSA-Lyon
Lyon
France
Email: pierre.francois@insa-lyon.fr
Kent Watsen
Watsen Networks
Email: kent+ietf@watsen.net