Auditing of Logon-Logoff: IPsec Main Mode events on failure should be enabled or disabled as appropriate. Audit IPsec Main Mode, which determines whether the operating system generates events for the results of the Internet Key Exchange (IKE) protocol and Authenticated Internet Protocol (AuthIP) during Main Mode negotiations. IKE is an Internet standard, defined in RFC 2409, that defines a mechanism to establish IPsec security associations (SAs). An SA is a combination of a mutually agreeable policy and keys that define the security services and mechanisms that help protect communication between IPsec peers. AuthIP is an enhanced version of IKE that offers additional flexibility with support for user-based authentication, authentication with multiple credentials, improved authentication method negotiation, and asymmetric authentication. Like IKE, AuthIP supports Main Mode and Quick Mode negotiation. Main Mode Internet Key Exchange (IKE) negotiation establishes a secure channel, known as the Internet Security Association and Key Management Protocol (ISAKMP) security association (SA), between two computers. To establish the secure channel, Main Mode negotiation determines a set of cryptographic protection suites, exchanges keying material to establish the shared secret key, and authenticates computer identities. Fix: (1) GPO: Commandline: auditpol.exe (2) REG: NO INFO