RFC 4252 · PROPOSED STANDARD · 2006

The Secure Shell Authentication Protocol

Overview

RFC 4252, “The Secure Shell Authentication Protocol”, is a Proposed Standard document published in January 2006 by T. Ylonen, C. Lonvick. It has since been updated by RFC 8308, RFC 8332. The canonical text is published by the RFC Editor.

Abstract

The Secure Shell Protocol (SSH) is a protocol for secure remote login and other secure network services over an insecure network. This document describes the SSH authentication protocol framework and public key, password, and host-based client authentication methods. Additional authentication methods are described in separate documents. The SSH authentication protocol runs on top of the SSH transport layer protocol and provides a single authenticated tunnel for the SSH connection protocol. [STANDARDS-TRACK]

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 4252 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Updated by
RFC 8308 RFC 8332
Other RFCs from 2006

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