Extensible Provisioning Protocol (EPP) Transport over QUIC
draft-ietf-regext-epp-quic-09

Internet Engineering Task Force                                   J. Yao
Internet-Draft                                                     H. Li
Intended status: Standards Track                                M. Zhang
Expires: 10 December 2026                                          CNNIC
                                                             D. Keathley
                                                                J. Gould
                                                          VeriSign, Inc.
                                                             8 June 2026

       Extensible Provisioning Protocol (EPP) Transport over QUIC
                     draft-ietf-regext-epp-quic-09

Abstract

   This document specifies how an Extensible Provisioning Protocol (EPP)
   session is mapped onto a QUIC connection.  EPP over QUIC (EoQ)
   leverages features of the QUIC protocol.

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
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   This Internet-Draft will expire on 10 December 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
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   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Session Management  . . . . . . . . . . . . . . . . . . . . .   4
   4.  Message Exchange  . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Data Unit Format  . . . . . . . . . . . . . . . . . . . . . .   8
   6.  EoQ Connection Start Packet . . . . . . . . . . . . . . . . .   8
   7.  Transport Considerations  . . . . . . . . . . . . . . . . . .   9
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
     8.1.  Registration of an EoQ Identification String  . . . . . .  10
     8.2.  Registration of Port Number . . . . . . . . . . . . . . .  10
   9.  Implementation Status . . . . . . . . . . . . . . . . . . . .  10
     9.1.  Verisign EPP SDK  . . . . . . . . . . . . . . . . . . . .  11
   10. Operational Considerations  . . . . . . . . . . . . . . . . .  11
     10.1.  Clients Fall Back with Management of Multiple
            Transport  . . . . . . . . . . . . . . . . . . . . . . .  11
     10.2.  Port Reuse . . . . . . . . . . . . . . . . . . . . . . .  12
     10.3.  QUIC Support Announcement and Discovery  . . . . . . . .  12
     10.4.  Configuration Parameters . . . . . . . . . . . . . . . .  12
     10.5.  Diagnostic and Troubleshooting . . . . . . . . . . . . .  12
     10.6.  Address Validation . . . . . . . . . . . . . . . . . . .  13
     10.7.  Authentication Considerations  . . . . . . . . . . . . .  13
     10.8.  0-RTT and Session Resumption . . . . . . . . . . . . . .  13
     10.9.  MTU and Fragmentation  . . . . . . . . . . . . . . . . .  14
   11. Security Considerations . . . . . . . . . . . . . . . . . . .  14
   12. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  14
   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     13.1.  Normative References . . . . . . . . . . . . . . . . . .  14
     13.2.  Informative References . . . . . . . . . . . . . . . . .  15
   Appendix A.  Change History . . . . . . . . . . . . . . . . . . .  15
     A.1.  Change from 00 to 01  . . . . . . . . . . . . . . . . . .  15
     A.2.  Change from 01 to 02  . . . . . . . . . . . . . . . . . .  15
     A.3.  Change from 02 to 03  . . . . . . . . . . . . . . . . . .  16
     A.4.  draft-ietf-regext-epp-quic-00 . . . . . . . . . . . . . .  16
     A.5.  draft-ietf-regext-epp-quic-01 . . . . . . . . . . . . . .  16
     A.6.  draft-ietf-regext-epp-quic-02 . . . . . . . . . . . . . .  16
     A.7.  draft-ietf-regext-epp-quic-03 . . . . . . . . . . . . . .  17
     A.8.  draft-ietf-regext-epp-quic-04 . . . . . . . . . . . . . .  17

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     A.9.  draft-ietf-regext-epp-quic-05 . . . . . . . . . . . . . .  17
     A.10. draft-ietf-regext-epp-quic-06 . . . . . . . . . . . . . .  17
     A.11. draft-ietf-regext-epp-quic-07 . . . . . . . . . . . . . .  17
     A.12. draft-ietf-regext-epp-quic-08 . . . . . . . . . . . . . .  18
     A.13. draft-ietf-regext-epp-quic-09 . . . . . . . . . . . . . .  18
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  18

1.  Introduction

   This document specifies how the Extensible Provisioning Protocol
   (EPP)[RFC5730] is mapped onto the QUIC transport [RFC9000].  QUIC is
   a network protocol that is based on UDP and incorporates native
   encryption support using TLS [RFC9001].  Though based on UDP, QUIC
   provides connection semantics like other stateful protocols.  This
   document discusses how EPP implementations can work with this and
   other features of QUIC while preserving the core EPP semantics.

   EPP sessions use a single QUIC stream for all command and response
   exchanges throughout the session lifecycle.  Unlike stateless
   transaction protocols that permit per-command independent streams,
   EPP is a stateful protocol with inherent sequential command
   dependencies defined in [RFC5730].  Maintaining a single stream
   preserves ordered transaction processing, consistent session state,
   and full compatibility with existing EPP operational and
   implementation models.

2.  Terminology

   This document makes use of the following terms:

   EoQ:  The acronym used for the EPP over QUIC transport that defines
      the use of QUIC as an EPP transport following the considerations
      in Section 2.1 of [RFC5730].

   EoQ connection:  Is a client-initiated bidirectional QUIC stream
      established on a QUIC connection using the "EoQ" Application-Layer
      Protocol Negotiation (ALPN) [RFC7301] value.  The EoQ connection
      maps to the client-server connection defined in Section 2.1 of
      [RFC5730], where the server returns an EPP <greeting>.  A single
      QUIC connection supports many EoQ connections.

   EoQ session:  Is an authenticated EoQ connection, which occurs after
      a successful EPP <login>.

   EoQ Connection Start Packet:  Used by clients to complete the

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      creation of an EoQ connection by signaling the server to create
      the QUIC stream and return the EPP <greeting> needed for an EPP
      connection.  Section 6 formally defines the EoQ Connection Start
      Packet.

   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.  Session Management

   Mapping EPP session management facilities onto the QUIC service is
   accomplished with a combination of a QUIC connection with the "EoQ"
   ALPN [RFC7301] value and client-initiated, bidirectional QUIC
   streams.  QUIC supports four stream types (Section 2.1 of [RFC9000]),
   but EoQ only supports the client-initiated, bidirectional stream
   type.

   An EPP session first requires creation of a QUIC connection between
   two peers, one that initiates the connection request and one that
   responds to the connection request.  The initiating peer is called
   the "client", and the responding peer is called the "server".  By
   default, an EPP server MUST listen for QUIC connection requests on a
   well-known UDP port number assigned by IANA (see Section 8.2), unless
   there is a mutual agreement to use another port number.

   A successfully established QUIC connection is secured by the native
   TLS support that QUIC provides using the "EoQ" ALPN value.

   Once the QUIC connection is established, the EPP client MUST then
   create a bidirectional QUIC stream by sending the EoQ Connection
   Start Packet (Section 6).  [RFC9000] states that "streams are created
   by sending data".  If the EPP server accepts the QUIC stream, it
   reads the EoQ Connection Start Packet (Section 6) and returns an EPP
   <greeting> to the client on the same QUIC stream.  After reading the
   EPP <greeting> message, and absent processing errors, the EPP client
   sends EPP commands and receives EPP responses on the same stream.  A
   QUIC stream corresponds to an EPP connection, which is referred to as
   an EoQ connection.  An authenticated QUIC stream, via a successful
   EPP <login>, corresponds to an EPP session, which is referred to as
   an EoQ session.

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   An EPP session is normally ended by the client issuing an EPP
   <logout> command.  A server receiving an EPP <logout> command MUST
   end the EPP session and close the QUIC stream.  A client MAY end an
   EoQ session by closing the QUIC stream and the server MUST end the
   EoQ session by closing the QUIC stream.

   EoQ connections are established as described in the QUIC transport
   specification [RFC9000].  During connection establishment, EoQ
   support is indicated using the "EoQ" ALPN value in the cryptographic
   handshake.

   A single QUIC connection may allow multiple QUIC streams.  This means
   that a single QUIC connection may support multiple EoQ sessions.  A
   server MAY limit the life span of an established EoQ session.  EoQ
   sessions that are inactive for more than a server-defined period MAY
   be ended by the server closing the QUIC stream.  A server MAY close
   EoQ sessions that have been open and active for longer than a server-
   defined limit.  Once the last QUIC stream for a QUIC connection is
   closed, the server MAY end the QUIC connection immediately.

4.  Message Exchange

   Except for the EPP server <greeting>, EPP messages are initiated by
   the EPP client in the form of EPP commands.  An EPP server MUST
   return an EPP response to an EPP command on the same QUIC stream that
   carried the command.  If the QUIC stream is closed after a server
   receives and successfully processes a command but before the response
   can be returned to the client, the server MAY attempt to undo the
   effects of the command to ensure a consistent state between the
   client and the server.  EPP commands are idempotent, so processing a
   command more than once produces the same net effect on the repository
   as successfully processing the command once.

   An EPP client streams EPP commands to an EPP server on an established
   QUIC stream.  A client MAY establish multiple QUIC streams to support
   multiple EoQ sessions with each EoQ session mapped to a single QUIC
   stream.  A server SHOULD limit a client to a maximum number of QUIC
   streams per QUIC connection based on server capabilities and
   operational load.  Absent such limit, a server may be subject to
   overload and resource exhaustion.

   EPP describes client-server interaction as a command-response
   exchange where the client sends one command to the server and the
   server returns one response to the client.

   Each EPP data unit MUST contain a single EPP message.  Commands MUST
   be processed independently.

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   A server SHOULD impose a limit on the amount of time required for a
   client to issue a well-formed EPP command to reduce the risk
   associated with a resource exhaustion attack.  Absent local policy, a
   server SHOULD end an EoQ session and close the QUIC stream if a well-
   formed command is not received within the time limit.

   A general state machine for an EPP server is described in Section 2
   of [RFC5730].  A general client-server message exchange using QUIC
   transport is illustrated in Figure 1.  It shows an example of
   successful exchange over a single QUIC stream of a QUIC connection.
   Many QUIC streams may be opened and closed during the life of a QUIC
   connection.

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                       Client                  Server
                  |                                     |
                  |      Successful QUIC Connection     |
                  | <<------------------------------->> |
                  |                                     |
                  |     Successful QUIC Stream with     |
                  |     EoQ Connection Start Packet     |
                  | <<------------------------------->> |
                  |                                     |
                  |             Send Greeting           |
                  | <<-------------------------------<< |
                  |                                     |
                  |             Send <login>            |
                  | >>------------------------------->> |
                  |                                     |
                  |             Send Response           |
                  | <<-------------------------------<< |
                  |                                     |
                  |            Send Command X           |
                  | >>------------------------------->> |
                  |                                     |
                  |            Send Response X          |
                  | <<-------------------------------<< |
                  |                                     |
                  |            Send Command Y           |
                  | >>------------------------------->> |
                  |                                     |
                  |            Send Response Y          |
                  | <<-------------------------------<< |
                  |                  .                  |
                                     .
                                     .
                  |            Send <logout>            |
                  | >>------------------------------->> |
                  |                                     |
                  |            Send Response            |
                  | <<-------------------------------<< |
                  |                                     |
                  |          Close QUIC Stream          |
                  | <<------------------------------->> |
                  |                                     |
                  |        Close QUIC Connection        |
                  | <<------------------------------->> |

     Figure 1: Example of Successful QUIC Client-Server Message Exchange

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   The EPP server MUST follow the "EPP Server State Machine" procedure
   described in [RFC5730].

5.  Data Unit Format

   The EPP data unit contains two fields: a 32-bit header that describes
   the total length of the data unit, and the EPP XML instance.  The
   length of the EPP XML instance is determined by subtracting four
   octets from the total length of the data unit.  A receiver must
   successfully read that many octets to retrieve the complete EPP XML
   instance before processing the EPP message.  The EPP Data Unit Format
   is depicted in Figure 2 (one tick mark represents one bit position).

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Total Length                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         EPP XML Instance                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                             Figure 2: EPP Data Unit Format

   The description of the fields shown in Figure 2 is as follows:

   Total Length (32 bits): The total length of the EPP data unit
   measured in octets in network (big endian) byte order.  The octets
   contained in this field MUST be included in the total length
   calculation.

   EPP XML Instance (variable length): The EPP XML instance carried in
   the data unit.

6.  EoQ Connection Start Packet

   The EoQ Connection Start Packet is written by the client after
   creating a QUIC stream to signal to the server to create the QUIC
   stream.  Absent processing errors or local policy, the server accepts
   the QUIC stream, reads the EoQ Connection Start Packet, and returns
   the EPP <greeting> to the client on same QUIC stream.

   The EoQ Connection Start Packet follows the Data Unit Format
   (Section 5) with two fields: a 32-bit header that describes the total
   length of the data unit, and the constant value of "EoQ Connection
   Start" instead of an "EPP XML Instance".  The length of a valid data
   unit MUST be 24 octets that includes 4 octets for the Total Length
   and 20 octets for the "EoQ Connection Start" constant value.

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7.  Transport Considerations

   Section 2.1 of [RFC5730] describes considerations to be addressed by
   protocol transport mappings.  This document addresses each of those
   considerations using a combination of features of the QUIC protocol
   and features of this document as discussed below:

   *  Command Order: QUIC guarantees ordered processing of data within
      each stream.  Section 2 of [RFC9000] describes streams in detail.

   *  Session Mapping: EPP session management utilizes QUIC streams and
      is described in Section 3

   *  Stateful Nature: QUIC supports stateful communications between
      endpoints via Connection IDs and long-lived streams within each
      connection.  Sections 2 and 5 of [RFC9000] describe these
      features, respectively.

   *  Frame Data Units: EoQ uses the packet framing defined in
      Section 5.

   *  Congestion Avoidance: QUIC provides various mechanisms to help
      achieve congestion avoidance.  [RFC9002] describes these
      mechanisms in detail.

   *  Reliability: QUIC uses message acknowledgement, packet
      retransmission, and other features to ensure reliability.
      Section 13 of [RFC9000] describes these features in detail.

   *  Pipelining: Pipelining is allowed in EoQ.  QUIC streams support
      sending multiple frames without waiting for responses from the
      other peer.  This does not change the basic single command, single
      response operating mode of the core EPP.

      Commands MUST be processed independently and in the same order as
      sent from the client.

      Batch-oriented processing (combining multiple EPP commands in a
      single data unit) is not permitted.  Each EPP data unit must
      contain a single EPP message.

      An EPP x5zz "Connection Management" error response, defined in
      Section 3 of [RFC5730], of a well-formed EPP client packet results
      in the server closing the EoQ connection after returning the error
      response.  A malformed EPP client packet results in the server
      closing the EoQ connection without providing an error response.
      All subsequent EPP commands sent on the EoQ connection will not be
      processed.

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8.  IANA Considerations

   RFC Editor Note: Please replace all occurrences of XXXX with the RFC
   number to be assigned to this document.

8.1.  Registration of an EoQ Identification String

   This document creates a new registration for the identification of
   EoQ in the "TLS Application-Layer Protocol Negotiation (ALPN)
   Protocol IDs" registry under Transport Layer Security (TLS)
   Extensions registry group available at
   https://www.iana.org/assignments/tls-extensiontype-values/.

   *  Protocol: EoQ

   *  Identification Sequence: 0x45 0x6F 0x51 ("EoQ")

   *  Reference: RFC XXXX

8.2.  Registration of Port Number

   The "Service Name and Transport Protocol Port Number Registry"
   (https://www.iana.org/assignments/service-names-port-numbers/)
   contains an entry for EPP UDP/700.  However, no known implementations
   of EPP over UDP exist.  This document requests IANA to update that
   entry so that it is reassigned to EPP and add a reference to this
   document.

   *  Service Name: epp

   *  Port Number: 700

   *  Transport Protocol(s): UDP

   *  Assignee: IESG

   *  Contact: IETF Chair

   *  Description: EPP run over QUIC

   *  Reference: [RFC5734] RFC XXXX

9.  Implementation Status

   Note to RFC Editor: Please remove this section and the reference to
   RFC 7942 [RFC7942] before publication.

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   This section records the status of known implementations of the
   protocol defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in RFC 7942
   [RFC7942].  The description of implementations in this section is
   intended to assist the IETF in its decision processes in progressing
   drafts to RFCs.  Please note that the listing of any individual
   implementation here does not imply endorsement by the IETF.
   Furthermore, no effort has been spent to verify the information
   presented here that was supplied by IETF contributors.  This is not
   intended as, and must not be construed to be, a catalog of available
   implementations or their features.  Readers are advised to note that
   other implementations may exist.

   According to RFC 7942 [RFC7942], "this will allow reviewers and
   working groups to assign due consideration to documents that have the
   benefit of running code, which may serve as evidence of valuable
   experimentation and feedback that have made the implemented protocols
   more mature.  It is up to the individual working groups to use this
   information as they see fit".

9.1.  Verisign EPP SDK

   Organization: Verisign Inc.

   Name: Verisign EPP SDK

   Description: The Verisign EPP SDK includes both a full client
   implementation and a full server stub implementation of this
   specification.

   Level of maturity: Development

   Coverage: All aspects of the protocol are implemented with QUIC V1.

   Licensing: GNU Lesser General Public License

   Contact: jgould@verisign.com

   URL: https://www.verisign.com/resources/registrar-resources/epp-sdk/

10.  Operational Considerations

10.1.  Clients Fall Back with Management of Multiple Transport

   If the establishment of an EoQ connection fails, clients MAY attempt
   to fall back to EPP over TCP as specified in [RFC5734], depending on
   local deployment and security policy.  It is up to clients to
   determine the mix of transports that best meets their business needs.

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10.2.  Port Reuse

   Although [RFC5734] does only a request for TCP, the companion UDP
   number was also allocated.  That practice was prior to [RFC6335] when
   TCP and UDP port numbers were simultaneously assigned when either was
   requested.  Section 8.2 updates EPP UDP/700 allocation to be used for
   EoQ.  This update does not introduce any operational issues given
   that there are no known implementations of EPP over UDP that exist.

10.3.  QUIC Support Announcement and Discovery

   There is no dedicated in-band mechanism defined in this specification
   for a server to explicitly announce EoQ support to clients.
   Operators MAY use out-of-band configuration or provisioning channels
   to advertise server EoQ support to clients in advance.

10.4.  Configuration Parameters

   Implementations MAY configure operational parameters to control EoQ
   session behavior.  These parameters can include idle session timeout,
   maximum QUIC streams per connection,command processing timeout, and
   maximum session timeout.  Servers and clients SHOULD align
   configuration limits to avoid session disruption and resource
   exhaustion.

   Implementation Note: There is no in-band protocol mechanism to align
   limits.  Operators typically distribute standard settings via SDKs.
   Client timeout and stream limits shall be set lower than server
   values for graceful connection handling.  Timeout rules are
   consistent across EoT and EoQ; per-connection stream limits are newly
   introduced in EoQ.

10.5.  Diagnostic and Troubleshooting

   Operators SHOULD log EoQ connection establishment status, stream
   lifecycle events, and command transaction results for diagnostic
   purposes.  QUIC transport errors and EPP protocol failures ought to
   be distinguishable to facilitate efficient troubleshooting.
   Implementations MAY provide granular error reporting to help identify
   session termination, connection timeout, and stream closure root
   causes.  Operators MUST redact sensitive data in the logs, such as
   user credentials and authorization information values.

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10.6.  Address Validation

   EoQ implementations MUST follow the address validation requirements
   defined in Section 8 of [RFC9000] to mitigate potential amplification
   attacks and validate client address reachability.  EoQ servers MUST
   utilize the QUIC Retry Packet mechanism described in Section 8.1.2 of
   [RFC9000] to perform return routability checks on client source
   addresses before accepting EoQ stream creation.  After successful
   address validation, EoQ servers MAY send NEW_TOKEN frames as
   specified in Section 8.1.3 of [RFC9000], allowing subsequent
   connection attempts from the same client address to avoid the 1-RTT
   validation delay.

10.7.  Authentication Considerations

   EoQ relies on the TLS authentication mechanisms defined in [RFC9001]
   for peer authentication and credential validation.  Implementations
   MUST follow the same authentication practices specified for EPP over
   TLS in [RFC5734].  Server and client authentication procedures remain
   unchanged from existing EPP deployment models when running over QUIC
   transport.

10.8.  0-RTT and Session Resumption

   Using 0-RTT for EoQ allows clients to establish connections and
   initiate EPP transactions without round-trip delay, enabling servers
   to use shorter idle timers and reduce connection overhead.  Session
   resumption and 0-RTT introduce privacy and replay risks.  EoQ
   implementations SHOULD follow [RFC8446] and [RFC9001] guidance to
   balance performance and risk mitigation.  Failure to do so increases
   privacy exposure and replay attack risks.  Clients SHOULD use session
   tickets only once and avoid resumption when network connectivity
   changes.  Reusing tickets or resuming sessions across changed
   networks raises replay vulnerabilities.  Clients MAY use NEW_TOKEN
   tokens per [RFC9000], but SHOULD restrict their use to session
   resumption scenarios.  Improper use of NEW_TOKEN frames disrupts
   session management and increases server load.  Servers SHOULD issue
   session tickets with a reasonable lifetime and implement anti-replay
   mechanisms for 0-RTT traffic.  Failure to deploy these controls will
   result in exploitable replay attacks.

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10.9.  MTU and Fragmentation

   EoQ implementations MUST follow the MTU and fragmentation guidance
   defined in [RFC9000].  Operators are encouraged to provision network
   paths with appropriate MTU sizes to avoid packet fragmentation for
   EPP message delivery.  Oversized EPP data units that exceed path MTU
   require proper QUIC fragmentation handling to maintain transmission
   reliability.

11.  Security Considerations

   EPP over QUIC provides the similar security with EPP over TCP with
   TLS.  Some related security issues have been discussed in [RFC5734]
   and [RFC9000].

   EoQ servers run the risk of a resource exhaustion attack by allowing
   the creation of unlimited QUIC streams per QUIC connection.  As
   indicated in Section 10.4, servers should limit a client to a maximum
   number of QUIC streams per QUIC connection based on server
   capabilities and operational load.  Absent such limit, the server may
   be subject to overload that would exhaust its resources.

12.  Acknowledgements

   The authors wish to thank the following persons for their feedback
   and suggestions: Scott Hollenbeck, Lucas Pardue, Martin Thompson, and
   Mohamed Boucadair.

13.  References

13.1.  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>.

   [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
              STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
              <https://www.rfc-editor.org/info/rfc5730>.

   [RFC5734]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
              Transport over TCP", STD 69, RFC 5734,
              DOI 10.17487/RFC5734, August 2009,
              <https://www.rfc-editor.org/info/rfc5734>.

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   [RFC6335]  Cotton, M., Eggert, L., Touch, J., Westerlund, M., and S.
              Cheshire, "Internet Assigned Numbers Authority (IANA)
              Procedures for the Management of the Service Name and
              Transport Protocol Port Number Registry", BCP 165,
              RFC 6335, DOI 10.17487/RFC6335, August 2011,
              <https://www.rfc-editor.org/info/rfc6335>.

   [RFC7301]  Friedl, S., Popov, A., Langley, A., and E. Stephan,
              "Transport Layer Security (TLS) Application-Layer Protocol
              Negotiation Extension", RFC 7301, DOI 10.17487/RFC7301,
              July 2014, <https://www.rfc-editor.org/info/rfc7301>.

   [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>.

   [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>.

   [RFC9001]  Thomson, M., Ed. and S. Turner, Ed., "Using TLS to Secure
              QUIC", RFC 9001, DOI 10.17487/RFC9001, May 2021,
              <https://www.rfc-editor.org/info/rfc9001>.

   [RFC9002]  Iyengar, J., Ed. and I. Swett, Ed., "QUIC Loss Detection
              and Congestion Control", RFC 9002, DOI 10.17487/RFC9002,
              May 2021, <https://www.rfc-editor.org/info/rfc9002>.

13.2.  Informative References

   [RFC7942]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", BCP 205,
              RFC 7942, DOI 10.17487/RFC7942, July 2016,
              <https://www.rfc-editor.org/info/rfc7942>.

Appendix A.  Change History

A.1.  Change from 00 to 01

   1.  Added Dan Keathley and James Gould as co-authors and aligned the
       draft with EPP RFC 5734.

A.2.  Change from 01 to 02

   1.  Make the clear distinction between an EPP connection and an EPP
       session for EoQ in the Session Management section.

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   2.  Align the handling of the EPP <logout> command with RFC 5734, by
       including "A client MAY end an EoQ session by closing the QUIC
       stream" in the Session Management section.
   3.  Ensure that the relationship of the EoQ connection and the EoQ
       stream is maintained with the sentence "This means that a single
       QUIC connection may support multiple EoQ sessions" in the Session
       Management section.
   4.  Leverage the EoQ session in place of the more generic EPP session
       in the Message Exchange section.

A.3.  Change from 02 to 03

   1.  Added the definition and use of the EoQ Connection Start Packet
       to explicitly trigger the creation of the QUIC stream and the EoQ
       connection to the server.
   2.  Added the Implementation Status section with the Verisign EPP SDK
       implementation.

A.4.  draft-ietf-regext-epp-quic-00

   1.  updated to WG document

A.5.  draft-ietf-regext-epp-quic-01

   1.  add section 8.1.  EPP Extension Registry

A.6.  draft-ietf-regext-epp-quic-02

   Incorporated feedback from Lucas Pardue:

   1.  Added a list of terms in Section 2 "Conventions Used in This
       Document".
   2.  Changed ALPN "eoq" value to "eoq/0.1" to support versioning,
       which will be changed to "eoq/1.0" once passing WGLC.
   3.  Changed "A client MAY end an EoQ session by closing the QUIC
       stream" to "A client MAY end an EoQ session by closing the QUIC
       stream and the server MUST end the EoQ session by closing the
       QUIC stream".
   4.  Added language to Section 3 "Session Management" to make it clear
       that a bidirectional QUIC stream is client-initiated and
       inclusion of the "eoq/0.1" ALPN was added for the QUIC
       connection.
   5.  Added "QUIC supports four stream types, but EoQ only supports the
       client-initiated, bidirectional stream type." to Section 3
       "Session Management" to be clear the stream types supported by
       EoQ.

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A.7.  draft-ietf-regext-epp-quic-03

   Nit fixes, such as spelling fixes and small wording changes.

A.8.  draft-ietf-regext-epp-quic-04

   Incorporated feedback from Martin Thompson:

   1.  Changed ALPN "eoq/0.1" value to "EoQ" to match the value of "DoQ"
       for DNS over QUIC in RFC 9250, which doesn't include versioning.
   2.  Added a reference to section 5 "Data Unit Format" in Section 7
       for defining the packet framing of EoQ.
   3.  Address the additional pipelining considerations (independent
       command processing, batching, error in processing commands).

   In the IANA Considerations section, removed the registration of the
   EoQ transport in the EPP Extension Registry.

A.9.  draft-ietf-regext-epp-quic-05

   Incorporated feedback from the Working Group Last Call (WGLC):

   1.  Made references consistent for the ALPN "EoQ" value with a
       reference to RFC 7301.
   2.  Add missing comma in the Acknowledgments section between Scott
       Hollenbeck and Lucas Pardue.
   3.  Removed normative reference to RFC 7451.

A.10.  draft-ietf-regext-epp-quic-06

   Incorporated feedback from the document shepherd review:

   1.  Updated the Verisign EPP SDK link to
       "https://www.verisign.com/resources/registrar-resources/epp-
       sdk/".
   2.  Updated Section 2 "Conventions Used in This Document" to
       reference RFC 2119 and RFC 8174.

A.11.  draft-ietf-regext-epp-quic-07

   Update the draft based on AD's comments:

   1.  Refine the texts.
   2.  Add the Operational Considerations section.

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A.12.  draft-ietf-regext-epp-quic-08

   Refine the texts based on AD's further comments

A.13.  draft-ietf-regext-epp-quic-09

   Refine the texts based on AD's comments

Authors' Addresses

   Jiankang Yao
   CNNIC
   4 South 4th Street,Zhongguancun,Haidian District
   Beijing
   Beijing, 100190
   China
   Phone: +86 10 59116505
   Email: yaojk@cnnic.cn

   Hongtao Li
   CNNIC
   4 South 4th Street,Zhongguancun,Haidian District
   Beijing
   Beijing, 100190
   China
   Email: lihongtao@cnnic.cn

   Man Zhang
   CNNIC
   4 South 4th Street,Zhongguancun,Haidian District
   Beijing
   Beijing, 100190
   China
   Email: zhangman@cnnic.cn

   Daniel Keathley
   VeriSign, Inc.
   12061 Bluemont Way
   Reston, VA 20190
   United States of America
   Email: dkeathley@verisign.com
   URI:   http://www.verisigninc.com

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   James Gould
   VeriSign, Inc.
   12061 Bluemont Way
   Reston, VA 20190
   United States of America
   Email: jgould@verisign.com
   URI:   http://www.verisigninc.com

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