QUIC New Server Preferred Address
draft-munizaga-quic-new-preferred-address-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Marco Munizaga , Marten Seemann | ||
| Last updated | 2025-10-15 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
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draft-munizaga-quic-new-preferred-address-00
QUIC M. Munizaga
Internet-Draft Ethereum Foundation
Intended status: Standards Track M. Seemann
Expires: 18 April 2026 Smallstep
15 October 2025
QUIC New Server Preferred Address
draft-munizaga-quic-new-preferred-address-00
Abstract
This document specifies an extension to QUIC to allow a server to
request a migration to a new preferred address.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at
https://marcopolo.github.io/new-preferred-address/draft-munizaga-
quic-new-preferred-address.html. Status information for this
document may be found at https://datatracker.ietf.org/doc/draft-
munizaga-quic-new-preferred-address/.
Discussion of this document takes place on the QUIC Working Group
mailing list (mailto:quic@ietf.org), which is archived at
https://mailarchive.ietf.org/arch/browse/quic/. Subscribe at
https://www.ietf.org/mailman/listinfo/quic/.
Source for this draft and an issue tracker can be found at
https://github.com/MarcoPolo/new-preferred-address.
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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Copyright Notice
Copyright (c) 2025 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/
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3
3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Negotiating Extension Use . . . . . . . . . . . . . . . . . . 3
5. New Preferred Address Frame . . . . . . . . . . . . . . . . . 4
6. Security Considerations . . . . . . . . . . . . . . . . . . . 4
6.1. Request Forgery Attacks . . . . . . . . . . . . . . . . . 5
6.2. DDoS - Thundering herd . . . . . . . . . . . . . . . . . 5
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
7.1. QUIC Transport Parameter . . . . . . . . . . . . . . . . 5
7.2. QUIC Frame Types . . . . . . . . . . . . . . . . . . . . 5
8. Normative References . . . . . . . . . . . . . . . . . . . . 6
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 6
TODOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
The QUIC transport protocol allows a client to migrate connections at
any time to any new address (Section 9 of [QUIC-TRANSPORT]). This
allows the connection to survive changes to the client's address.
QUIC also allows a server to migrate to a different address, but only
a single time, and only to an address specified at the start of a
connection via the Server's Preferred Address (Section 9.6 of
[QUIC-TRANSPORT]). For some applications, including those where the
server and client are peers, limiting the server to only a single
migration at the beginning is too limiting. This document specifies
an extension to QUIC to allow a server to request a migration to a
new preferred address.
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This document defines a new transport parameter that indicates
support of this extension and specifies a new frame type to inform
the client of the server's new preferred address.
2. Conventions and Definitions
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. Motivation
In peer to peer networks, the role of server and client is arbitrary.
An endpoint may serve as a client in one connection and a server in
another. Limiting connection migration to clients limits the
flexibility of endpoints in this network. A peer in this network
would like to migrate all of its connections, not just the ones it
happens to be a client in.
While it is not the primary goal, this extension may also assist in
NAT traversal by migrating to a dynamically chosen server address. A
server could have a client connect over a relay, and later migrate to
a direct connection after applying NAT traversal techniques. The
specific NAT traversal techniques are out of scope of this document.
4. Negotiating Extension Use
new_preferred_address (0xff0969d85c):
Clients advertise their support of this extension by sending the
new_preferred_address (0xff0969d85c) transport parameter (Section 7.4
of [QUIC-TRANSPORT]) with an empty value. Sending this transport
parameter signals to the server that the client understands the
NEW_PREFERRED_ADDRESS frame.
Servers MUST NOT send this transport parameter. A client that
supports this extension and receives this transport parameter MUST
abort the connection with a TRANSPORT_PARAMETER_ERROR.
Endpoints MUST NOT remember the value of this extension for 0-RTT.
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5. New Preferred Address Frame
A server can use an NEW_PREFERRED_ADDRESS frame to request the client
to migrate the connection to the provided server address. Upon
receiving an NEW_PREFERRED_ADDRESS, the client MAY initiate
migration. If the client does migrate it MUST adhere to the client
behavior defined in Section 9.6 of [QUIC-TRANSPORT].
The NEW_PREFERRED_ADDRESS is defined as follows:
NEW_PREFERRED_ADDRESS Frame {
Type (i) = 0x1d5845e2,
Sequence Number (i),
IPv4 Address (32),
IPv4 Port (16),
IPv6 Address (128),
IPv6 Port (16),
}
Following the common frame format described in Section 12.4 of
[QUIC-TRANSPORT], NEW_PREFERRED_ADDRESS frames have a type of
0x1d5845e2, and contain the following fields:
Sequence Number: A variable-length integer representing the sequence
number assigned to the NEW_PREFERRED_ADDRESS frame by the sender
so receivers can ignore obsolete frames. A sending endpoint MUST
send monotonically increasing values in the Sequence Number field
to allow obsolete NEW_PREFERRED_ADDRESS frames to be ignored when
packets are processed out of order.
IPv4 and IPv6 Address and Port: Analogous to the preferred_address
transport parameter, this frame contains an address and port for
both IPv4 and IPv6. The four-byte IPv4 Address field is followed
by the associated two-byte IPv4 Port field. This is followed by a
16-byte IPv6 Address field and two-byte IPv6 Port field.
NEW_PREFERRED_ADDRESS frames are ack-eliciting, and MUST only be sent
in the application data packet number space.
The server SHOULD ensure that its peer has a sufficient number of
available and unused connection IDs, as the client will be unable to
migrate without an unused connection ID. The server MAY bundle a
NEW_CONNECTION_ID frame with the NEW_PREFERRED_ADDRESS. Likewise,
the client should ensure the same to allow the server to probe new
paths.
6. Security Considerations
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6.1. Request Forgery Attacks
The same considerations from Section 21.5 of [QUIC-TRANSPORT] apply
here as well.
6.2. DDoS - Thundering herd
A malicious server could wait until it has received a large number of
clients, and request a migration from all of them at the same time to
a victim endpoint. If the clients all migrate at the same time, they
may overload or otherwise negatively impact the victim endpoint.
Clients may mitigate this by randomly delaying the migration.
7. IANA Considerations
7.1. QUIC Transport Parameter
This document registers the new_preferred_address transport parameter
in the "QUIC Transport Parameters" registry established in
Section 22.3 of [QUIC-TRANSPORT]. The following fields are
registered:
Value: 0xff0969d85c
Parameter Name: new_preferred_address
Status: Provisional
Specification: This document
Change Controller: IETF (iesg@ietf.org)
Contact: Marco Munizaga (marco@marcopolo.io)
7.2. QUIC Frame Types
This document registers one new value in the "QUIC Frame Types"
registry established in Section 22.4 of [QUIC-TRANSPORT]. The
following fields are registered:
Value: 0x1d5845e2
Frame Type Name: NEW_PREFERRED_ADDRESS
Status: Provisional
Specification: This document
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Change Controller: IETF (iesg@ietf.org)
Contact: Marco Munizaga (marco@marcopolo.io)
8. Normative References
[QUIC-TRANSPORT]
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/rfc/rfc9000>.
[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/rfc/rfc2119>.
[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/rfc/rfc8174>.
Acknowledgments
TODO acknowledge.
TODOs
Questions
* Any new security conserations from allowing a dynamically chosen
preferred address?
* Any new security conserations from allowing a deferred chosen
preferred address?
Authors' Addresses
Marco Munizaga
Ethereum Foundation
Email: marco@marcopolo.io
Marten Seemann
Smallstep
Email: martenseemann@gmail.com
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