RFC 6398 · BEST CURRENT PRACTICE · 2011

IP Router Alert Considerations and Usage

Overview

RFC 6398, “IP Router Alert Considerations and Usage”, is a Best Current Practice document published in October 2011 by F. Le Faucheur. It updates RFC 2113, RFC 2711. The canonical text is published by the RFC Editor.

Abstract

The IP Router Alert Option is an IP option that alerts transit routers to more closely examine the contents of an IP packet. The Resource reSerVation Protocol (RSVP), Pragmatic General Multicast (PGM), the Internet Group Management Protocol (IGMP), Multicast Listener Discovery (MLD), Multicast Router Discovery (MRD), and General Internet Signaling Transport (GIST) are some of the protocols that make use of the IP Router Alert Option. This document discusses security aspects and usage guidelines around the use of the current IP Router Alert Option, thereby updating RFC 2113 and RFC 2711. Specifically, it provides recommendations against using the Router Alert in the end-to-end open Internet and identifies controlled environments where protocols depending on Router Alert can be used safely. It also provides recommendations about protection approaches for service providers. Finally, it provides brief guidelines for Router Alert implementation on routers. This memo documents an Internet Best Current Practice.

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 6398 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 2113 RFC 2711
Other RFCs from 2011

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