How Does IP sec evaluate whether the access lists are mirrored as a requirement to negotiate its security association?

IPsec evaluates access lists by checking if the traffic matches specified criteria for encryption and authentication. During the negotiation of a Security Association (SA), IPsec ensures that the traffic flows defined in the access lists are consistent and mirrored between peers, meaning both sides should have identical rules. If the access lists do not match, the negotiation may fail, preventing the establishment of secure communication. This mirroring is crucial for ensuring that both ends of the connection handle the same traffic securely.