RFC 9319 · BEST CURRENT PRACTICE · 2022

The Use of maxLength in the Resource Public Key Infrastructure

Overview

RFC 9319, “The Use of maxLength in the Resource Public Key Infrastructure”, is a Best Current Practice document published in October 2022 by Y. Gilad, S. Goldberg, K. Sriram, J. Snijders, B. Maddison. The canonical text is published by the RFC Editor.

Abstract

This document recommends ways to reduce the forged-origin hijack attack surface by prudently limiting the set of IP prefixes that are included in a Route Origin Authorization (ROA). One recommendation is to avoid using the maxLength attribute in ROAs except in some specific cases. The recommendations complement and extend those in RFC 7115. This document also discusses the creation of ROAs for facilitating the use of Distributed Denial of Service (DDoS) mitigation services. Considerations related to ROAs and RPKI-based Route Origin Validation (RPKI-ROV) in the context of destination-based Remotely Triggered Discard Route (RTDR) (elsewhere referred to as "Remotely Triggered Black Hole") filtering are also highlighted.

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.

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