RFC 7401 · PROPOSED STANDARD · 2015

Host Identity Protocol Version 2

Overview

RFC 7401, “Host Identity Protocol Version 2”, is a Proposed Standard document published in April 2015 by R. Moskowitz, T. Heer, P. Jokela, T. Henderson. It obsoletes RFC 5201. It has since been updated by RFC 8002, RFC 9374. The canonical text is published by the RFC Editor.

Abstract

This document specifies the details of the Host Identity Protocol (HIP). HIP allows consenting hosts to securely establish and maintain shared IP-layer state, allowing separation of the identifier and locator roles of IP addresses, thereby enabling continuity of communications across IP address changes. HIP is based on a Diffie-Hellman key exchange, using public key identifiers from a new Host Identity namespace for mutual peer authentication. The protocol is designed to be resistant to denial-of-service (DoS) and man-in-the-middle (MitM) attacks. When used together with another suitable security protocol, such as the Encapsulating Security Payload (ESP), it provides integrity protection and optional encryption for upper-layer protocols, such as TCP and UDP.

This document obsoletes RFC 5201 and addresses the concerns raised by the IESG, particularly that of crypto agility. It also incorporates lessons learned from the implementations of RFC 5201.

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 7401 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 5201
Updated by
RFC 8002 RFC 9374
Other RFCs from 2015

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