Ssh2.0 Overview; Algorithm And Key - 3Com MSR 50 Series Configuration Manual

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SSH2.0 Overview

Algorithm and Key

SSH2.0 C
When configuring SSH2.0, go to these sections for information you are interested
in:
"SSH2.0 Overview" on page 1919
■
"Configuring the Device as an SSH Server" on page 1922
■
"Configuring the Device as an SSH Client" on page 1928
■
"Displaying and Maintaining the SSH Protocol" on page 1930
■
"SSH Server Configuration Example" on page 1931
■
"SSH Client Configuration Example" on page 1940
■
Secure shell (SSH) offers an approach to securely logging into a remote device. By
encryption and strong authentication, it protects devices against attacks such as IP
spoofing and plain text password interception.
The device can not only work as an SSH server to support connections with SSH
clients, but also work as an SSH client to allow users to establish SSH connections
with a remote device acting as the SSH server.
c
CAUTION: Currently, when acting as an SSH server, the device supports two SSH
versions: SSH2 and SSH1. When acting as an SSH client, the device supports SSH2
only.
Algorithm is a set of transformation rules for encryption and decryption.
Information without being encrypted is known as plain text, while information
that is encrypted is known as cipher text. Encryption and decryption are performed
using a string of characters called a key, which controls the transformation
between plain text and cipher text, for example, changing the plain text into
cipher text or cipher text into plain text.
Figure 558 Encryption and decryption
Plain text Plain text
Key-based algorithm is usually classified into symmetric key algorithm and
asymmetric key algorithm.
ONFIGURATION
Key Key
Cipher text Cipher text
Encryption Encryption
Key Key
Decryption Decryption
Plain text Plain text