RFC 8085 · BEST CURRENT PRACTICE · 2017

UDP Usage Guidelines

Overview

RFC 8085, “UDP Usage Guidelines”, is a Best Current Practice document published in March 2017 by L. Eggert, G. Fairhurst, G. Shepherd. It obsoletes RFC 5405. It has since been updated by RFC 8899. The canonical text is published by the RFC Editor.

Abstract

The User Datagram Protocol (UDP) provides a minimal message-passing transport that has no inherent congestion control mechanisms. This document provides guidelines on the use of UDP for the designers of applications, tunnels, and other protocols that use UDP. Congestion control guidelines are a primary focus, but the document also provides guidance on other topics, including message sizes, reliability, checksums, middlebox traversal, the use of Explicit Congestion Notification (ECN), Differentiated Services Code Points (DSCPs), and ports.

Because congestion control is critical to the stable operation of the Internet, applications and other protocols that choose to use UDP as an Internet transport must employ mechanisms to prevent congestion collapse and to establish some degree of fairness with concurrent traffic. They may also need to implement additional mechanisms, depending on how they use UDP.

Some guidance is also applicable to the design of other protocols (e.g., protocols layered directly on IP or via IP-based tunnels), especially when these protocols do not themselves provide congestion control.

This document obsoletes RFC 5405 and adds guidelines for multicast UDP usage.

Abstract as published in the RFC, via rfc-editor.org.

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

The canonical text of RFC 8085 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 5405
Updated by
RFC 8899
Other RFCs from 2017

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