RFC 4254 · PROPOSED STANDARD · 2006

The Secure Shell Connection Protocol

Overview

RFC 4254, “The Secure Shell Connection Protocol”, is a Proposed Standard document published in January 2006 by T. Ylonen, C. Lonvick. It has since been updated by RFC 8308. The canonical text is published by the RFC Editor.

Abstract

Secure Shell (SSH) is a protocol for secure remote login and other secure network services over an insecure network.

This document describes the SSH Connection Protocol. It provides interactive login sessions, remote execution of commands, forwarded TCP/IP connections, and forwarded X11 connections. All of these channels are multiplexed into a single encrypted tunnel.

The SSH Connection Protocol has been designed to run on top of the SSH transport layer and user authentication protocols. [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 4254 is hosted at rfc-editor.org. Available in TXT,HTML.

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

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