RFC 9063 · INFORMATIONAL · 2021

Host Identity Protocol Architecture

Overview

RFC 9063, “Host Identity Protocol Architecture”, is an Informational document published in July 2021 by R. Moskowitz, M. Komu. It obsoletes RFC 4423. The canonical text is published by the RFC Editor.

Abstract

This memo describes the Host Identity (HI) namespace, which provides a cryptographic namespace to applications, and the associated protocol layer, the Host Identity Protocol, located between the internetworking and transport layers, that supports end-host mobility, multihoming, and NAT traversal. Herein are presented the basics of the current namespaces, their strengths and weaknesses, and how a HI namespace will add completeness to them. The roles of the HI namespace in the protocols are defined.

This document obsoletes RFC 4423 and addresses the concerns raised by the IESG, particularly that of crypto agility. The Security Considerations section also describes measures against flooding attacks, usage of identities in access control lists, weaker types of identifiers, and trust on first use. This document incorporates lessons learned from the implementations of RFC 7401 and goes further to explain how HIP works as a secure signaling channel.

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

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 9063 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC obsoletes
RFC 4423
Other RFCs from 2021

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