Security Benefits (continued)

Data Integrity
Data integrity guarantees that data sent from one end of a transaction arrives unaltered at the other end. Even with Secure Shell encryption, the data being sent over the network could still be vulnerable to someone inserting unwanted data into the data stream (See Insertion and replay attacks for more details). Secure Shell version 2 (SSH2) uses Message Authentication Code (MAC) algorithms to greatly improve upon the original Secure Shell's (SSH1) simple 32-bit CRC data integrity checking method.

Other Benefits
Compression, another feature of the Secure Shell protocol, is performed prior to encryption and can significantly reduce the computational cost of encrypting data. Compression can also noticeably improve the efficiency of a connection and is especially beneficial in file transfers, X11 forwarding, and running curses-style programs.

Secure Shell provides helpful output or log messages. These messages can be turned on or off or be configured to give varying levels of detail. Log messages can prove very helpful when troubleshooting a problem. For example, if a client were unable to connect to a given server, this log output would be the first place to look to determine the source of the problem.