1] Interesting Traffic initiates the IPSec process. IPSec security policy configured in the IPSec peers starts the IKE process.
2] IKE phase 1. IKE authenticates IPSec peers and negotiates IKE SAs during this phase, setting up a secure channel for negotiating IPSec SAs in phase 2.
3] IKE phase 2. IKE negotiates IPSec SA parameters and sets up matching IPSec SAs in the peers.
4] Data transfer. Data is transferred between IPSec peers based on the IPSec parameters and keys stored in the SA database.
5] IPSec tunnel termination. IPSec SAs terminate through deletion or by timing out.
