Various Policy Parameters for IKE Phase 1

Once you are in ISAKMP configuration mode, you can enter your IKE parameters, such as authentication method, encryption algorithm, hash algorithm, and so on:

 R1 (config-isakmp)# ? 

Following is a list of ISAKMP commands:

Authentication	Set an authentication method for protection suite
Default	Set a command to its defaults
Encryption	Set an encryption algorithm for the protection suite
Exit	Exit from ISAKMP protection suite configuration mode
Group	Set the D-H group
Hash	Set the hash algorithm for the protection suite
Lifetime	Set the lifetime for the ISAKMP SA
No	Negate a command or set its defaults

Using the example earlier, the policy we defined for IKE Phase 1 appears in Table 8.3.

Table 8.3. IKE Phase 1 Configuration Parameters

Policy	R1 Configuration	R2 Configuration
Preshared key	cisco	cisco
Encryption algorithm	DES	DES
Hash algorithm	SHA-1	SHA-1
D-H group	Group 1	Group 1
Phase 1 lifetime	12 hours	12 hours

An example of an IKE phase 1 policy for R1 would be

 R1 (config)# crypto isakmp policy 10 R1 (config-isakmp)# authentication pre-share R1 (config-isakmp)# encryption des R1 (config-isakmp)# hash sha-1 R1 (config-isakmp)# group 1 R1 (config-isakmp)# lifetime 43200