Cisco Systems C7200 manual Transform type Description

Chapter 4 Configuring the VSA

Configuration Tasks

Table 4-1shows allowed transform combinations for the AH and ESP protocols.

Table 4-1 Allowed Transform Combinations

Transform type	Transform	Description
AH Transform (Pick up to one.)	ah-md5-hmac	AH with the MD5 (Message Digest 5)
		(HMAC variant) authentication algorithm
	ah-sha-hmac	AH with the SHA (Secure Hash Algorithm)
		(HMAC variant) authentication algorithm
ESP Encryption Transform (Note: If an ESP	esp-aes	ESP with the 128-bit Advanced Encryption
Authentication Transform is used, you must		Standard (AES) encryption algorithm
pick one.)	esp-aes 128	ESP with the 128-bit AES encryption algorithm
	esp-aes 192	ESP with the 192-bit AES encryption algorithm
	esp-aes 256	ESP with the 256-bit AES encryption algorithm
	esp-des	ESP with the 56-bit Data Encryption Standard
		(DES) encryption algorithm
	esp-3des	ESP with the 168-bit DES encryption algorithm
		(3DES or Triple DES)
	esp-null	Null encryption algorithm
ESP Authentication Transform (Pick up to	esp-md5-hmac	ESP with the MD5 (HMAC variant)
one.)		authentication algorithm
	esp-sha-hmac	ESP with the SHA (HMAC variant)
		authentication algorithm

Examples of acceptable transform combinations are as follows:

•ah-md5-hmac

•esp-des

•esp-3des and esp-md5-hmac

•ah-sha-hmac and esp-des and esp-sha-hmac

The parser will prevent you from entering invalid combinations; for example, once you specify an AH transform it will not allow you to specify another AH transform for the current transform set.

C7200 VSA (VPN Services Adapter) Installation and Configuration Guide

4-6 OL-9129-02