I know how to configure site-to-site VPN tunnel but I just want to know what really happens during Phase 1 and 2. This can really help during troubleshooting.
I understand that IKE phase 1 is used to establish IKE SAs. But I'm a little confused with the purpose of the Encryption and Hash functions when defining an ISAKMP Policy. Is this the encryption and hash that will be used during negotiation? Is the preshared key transmitted during Phase 1 or 2? What does really happen during Phase 1 or 2? Can someone help me understand this in detail? Thank you very much.