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Network Protocols Glossary

What is a network protocol? Protocols are the rules of the road for how data exists and moves on the network. They allow many different systems and computers to communicate.

Remote Shell (RSH) Protocol

What is Remote Shell (RSH) Protocol?

Remote Shell, is a legacy protocol used to execute commands on a remote host. It was a popular tool in the early days of networking, providing a basic method for remote administration. While RSH was once a convenient tool, its security flaws have rendered it obsolete in modern network environments.


What is the purpose of RSH

The RSH protocol operates on a simple client-server model:

Client Initiation: A user on a local machine initiates an RSH command, specifying the remote host and the command to be executed.

Authentication: RSH relies on a trust-based authentication mechanism. It checks the .rhosts file on the remote host to verify the requesting user's identity. This file contains a list of trusted hosts and users allowed to access the system without a password.

Connection Establishment: If authentication is successful, an unencrypted connection is established between the client and the remote host using TCP port 513.

Command Execution: The specified command is executed on the remote host, and its output is returned to the client.