RFC 9869 on Datagram Packetization Layer Path MTU Discovery (DPLPMTUD) for UDP Options

A new Request for Comments is now available in online RFC libraries.

        RFC 9869

        Title:      Datagram Packetization Layer Path MTU 
                    Discovery (DPLPMTUD) for UDP Options 
        Author:     G. Fairhurst,
                    T. Jones
        Status:     Standards Track
        Stream:     IETF
        Date:       October 2025
        Mailbox:    gorry@erg.abdn.ac.uk,
                    tom@erg.abdn.ac.uk
        Pages:      13
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-ietf-tsvwg-udp-options-dplpmtud-15.txt

        URL:        https://www.rfc-editor.org/info/rfc9869

        DOI:        10.17487/RFC9869

This document specifies how a UDP Options sender implements Datagram
Packetization Layer Path MTU Discovery (DPLPMTUD) as a robust method
for Path MTU Discovery (PMTUD). This method uses the UDP Options
packetization layer. It allows an application to discover the largest
size of datagram that can be sent across a network path. It also
provides a way to allow the application to periodically verify the
current Maximum Packet Size (MPS) supported by a path and to update
this when required.

This document is a product of the Transport and Services Working Group Working Group of the IETF.

This is now a Proposed Standard.

STANDARDS TRACK: This document specifies an Internet Standards Track
protocol for the Internet community, and requests discussion and suggestions
for improvements.  Please refer to the current edition of the Official
Internet Protocol Standards (https://www.rfc-editor.org/standards) for the 
standardization state and status of this protocol.  Distribution of this 
memo is unlimited.

This announcement is sent to the IETF-Announce and rfc-dist lists.
To subscribe or unsubscribe, see
  https://www.ietf.org/mailman/listinfo/ietf-announce
  https://mailman.rfc-editor.org/mailman/listinfo/rfc-dist

For searching the RFC series, see https://www.rfc-editor.org/search
For downloading RFCs, see https://www.rfc-editor.org/retrieve/bulk

Requests for special distribution should be addressed to either the
author of the RFC in question, or to rfc-editor@rfc-editor.org.  Unless
specifically noted otherwise on the RFC itself, all RFCs are for
unlimited distribution.

The RFC Editor Team