Network Working Group                                          T. Ylonen
INTERNET-DRAFT                                                T. Kivinen
draft-ietf-secsh-architecture-08.txt                         M. Saarinen
Expires: 2 September, 2001                                      T. Rinne
                                                             S. Lehtinen
                                             SSH Communications Security
                                                           2 March, 2001



            Secure Shell Remote Login Protocol Architecture

Status of This Memo

This document is an Internet-Draft and is in full conformance
with all provisions of Section 10 of RFC2026.

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Abstract

The Secure Shell Remote Login Protocol is a suite of protocols for
secure remote logins and other secure network services over an insecure
network.  This document describes the overall architecture of the Secure
Shell protocols, as well as the notation and terminology used in the
protocol documents. It also discusses the algorithm naming system that
allows local extensions.  The Secure Shell protocol consists of three
major components: The Transport Layer Protocol provides server authenti-
cation, confidentiality, and integrity with perfect forward secrecy. The
User Authentication Protocol authenticates the client to the server. The
Connection Protocol multiplexes the encrypted tunnel into several logi-
cal channels.  Details of these protocols are described in separate doc-
uments.









T. Ylonen, T. Kivinen, M. Saarinen, T. Rinne and S. Lehtinen    [page 1]

INTERNET-DRAFT                                            2 March, 2001

Table of Contents

1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . .  2
2.  Specification of Requirements   . . . . . . . . . . . . . . . . .  2
3.  Architecture  . . . . . . . . . . . . . . . . . . . . . . . . . .  3
  3.1.  Host Keys   . . . . . . . . . . . . . . . . . . . . . . . . .  3
  3.2.  Extensibility   . . . . . . . . . . . . . . . . . . . . . . .  4
  3.3.  Policy Issues   . . . . . . . . . . . . . . . . . . . . . . .  4
  3.4.  Security Properties   . . . . . . . . . . . . . . . . . . . .  5
  3.5.  Packet Size and Overhead  . . . . . . . . . . . . . . . . . .  5
  3.6.  Localization and Character Set Support  . . . . . . . . . . .  6
4.  Data Type Representations Used in the Secure Shell Protocols  . .  7
5.  Algorithm Naming  . . . . . . . . . . . . . . . . . . . . . . . .  8
6.  Message Numbers   . . . . . . . . . . . . . . . . . . . . . . . .  8
7.  IANA Considerations   . . . . . . . . . . . . . . . . . . . . . .  9
8.  Security Considerations   . . . . . . . . . . . . . . . . . . . . 10
9.  Trademark Issues  . . . . . . . . . . . . . . . . . . . . . . . . 10
10.  References   . . . . . . . . . . . . . . . . . . . . . . . . . . 10
11.  Authors' Addresses   . . . . . . . . . . . . . . . . . . . . . . 11