SSH Operation
(source : CCNA 2 V5 Chapter 2)

  • Secure Shell (SSH) is a protocol that provides a secure (encrypted) command-line based connection to a remote device
  • SSH is commonly used in UNIX-based systems
  • Cisco IOS also supports SSH
  • A version of the IOS software including cryptographic (encrypted) features and capabilities is required in order to enable SSH on Catalyst 2960 switches
  • Because its strong encryption features, SSH should replace Telnet for management connections
  • SSH uses TCP port 22 by default. Telnet uses TCP port 23