Integrity option

The Telnet protocol offer no form of detection of active attacks. This section suggests a way to detect active attacks using the standard Telnet option code scheme. Like the the encryption option, this option uses session keys exchanged during the authentication stage.

• Design goals
• The integrity information
• Placement in the protocol model
• Generating the integrity information
  • Integrity type: 32-bit CRC and IDEA in modified CFB mode
• Command name and codes
• Command meanings and usage
• Implementation rules