RFC 9131 · PROPOSED STANDARD · 2021

Gratuitous Neighbor Discovery: Creating Neighbor Cache Entries on First-Hop Routers

Overview

RFC 9131, “Gratuitous Neighbor Discovery: Creating Neighbor Cache Entries on First-Hop Routers”, is a Proposed Standard document published in October 2021 by J. Linkova. It updates RFC 4861. The canonical text is published by the RFC Editor.

Abstract

Neighbor Discovery (RFC 4861) is used by IPv6 nodes to determine the link-layer addresses of neighboring nodes as well as to discover and maintain reachability information. This document updates RFC 4861 to allow routers to proactively create a Neighbor Cache entry when a new IPv6 address is assigned to a node. It also updates RFC 4861 and recommends that nodes send unsolicited Neighbor Advertisements upon assigning a new IPv6 address. These changes will minimize the delay and packet loss when a node initiates connections to an off-link destination from a new IPv6 address.

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

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9131 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC updates
RFC 4861
Other RFCs from 2021

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