Configure an IPSec Tunnel Between a Checkpoint NG and Router - Cisco
Example for Configuring the Headquarters (Cisco Router) to Manage Branches Using Efficient VPN and Establishing IPSec Tunnels - AR100, AR120, AR150, AR160, AR200, AR1200, AR2200, AR3200, and AR3600 CLI-based Typical Configuration Examples -
Configuring a VPN Using Easy VPN and an IPSec Tunnel [Support] - Cisco Systems
Configuring IPSec Router-to-Router Hub and Spoke with Communication Between the Spokes - Cisco
how to configure site to site ipsec vpn using cisco packet tracer