Tag archive: GRE

Generic Route Encapsulation enables us bulding point to point tunnels. There are 2 kinds of tunnels GRE over IPSEC and IPSEC over GRE. They both work in tunnel mode by default but as we see in a while, work in completely different way.

There are 2 kinds of VPN IPSEC tunnels : Policy Based which is based on “crypto maps” and implementation them on the physical interfaces and Route Based which is based on virtual interfaces (tunnel interfaces). In this article I will talk them over, show how to implement them, when we may to pick up particular…