Imágenes de router, switch y ASA para las simulaciones
Introduction to Cisco IPsec TechnologyCisco IOS VPN Configuration Guide
Configure IKEv1 IPsec Site-to-Site Tunnels with the ASDM or CLI on the ASA
Implementing Layer 2 Tunnel Protocol Version 3
Point-to-Point GRE over IPsec Design Guide
Virtual Tunnel Interface Part 1
Virtual Tunnel Interface Part 2
Dynamic Multipoint VPN Configuration Guide