1-11 SSH ConfigurationThe DSA algorithm is newly added in SSH configuration. Click the following links for related information:z Generating/Destroying Key Pairsz Creating an SSH User and Specifying an Authentication Typez Configuring the Public Key of a Client on the ServerWhen configuring SSH, go to these sections for information you are interested:z SSH Overviewz SSH Server and Client Configuration Task Listz Displaying and Maintaining SSH Configurationz Comparison of SSH Commands with the Same Functionsz SSH Configuration ExamplesSSH OverviewIntroduction to SSHSecure Shell (SSH) is a protocol that provides secure remote login and other security services ininsecure network environments. In an SSH connection, data are encrypted before being sent out anddecrypted after they reach the destination. This prevents attacks such as plain text passwordinterception. Besides, SSH also provides powerful user authentication functions that prevent attackssuch as DNS and IP spoofing.SSH adopts the client-server model. The device can be configured as an SSH client or an SSH server.In the former case, the device establishes a remote SSH connection to an SSH server. In the latter case,the device provides connections to multiple clients.Furthermore, SSH can also provide data compression to increase transmission speed, take the place ofTelnet or provide a secure “channel” for FTP.z Currently, the device that serves as an SSH server supports two SSH versions: SSH2 and SSH1,and the device that serves as an SSH client supports only SSH2.z Unless otherwise noted, SSH refers to SSH2 throughout this document.Algorithm and KeyAlgorithm is a set of transformation rules for encryption and decryption. Information without beingencrypted is known as plain text, while information that is encrypted is known as cipher text. Encryption
