Hello Thierno
ISAKMP policies are not tied directly to the crypto map so the numbers don’t have to be the same. ISAKMP policies function as follows:
Each configuration supports a maximum of 20 ISAKMP policies, each with a different set of values. Assign a unique priority to each policy you create. The lower the priority number, the higher the priority.
When ISAKMP negotiations begin, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer tries to find a match. The remote peer checks all of the peer’s policies against each of its configured policies in priority order (highest priority first) until it discovers a match.
A match exists when both policies from the two peers contain the same encryption, hash, authentication, and Diffie-Hellman parameter values, and when the remote peer policy specifies a lifetime less than or equal to the lifetime in the policy the initiator sent. If the lifetimes are not identical, the security appliance uses the shorter lifetime. If no acceptable match exists, ISAKMP refuses negotiation and the SA is not established.
This was taken from the following Cisco documentation:
I hope this has been helpful!
Laz