Overview

Generic Routing Encapsulation (GRE) is a protocol designed for encapsulating and carrying the packets of one network layer protocol (for example, IP or IPX) over another network layer protocol (for example, IP). The path that transfers the encapsulated packets is referred to as a GRE tunnel.

A GER tunnel is a virtual point-to-point (P2P) connection. Packets are encapsulated at one end of the tunnel and de-encapsulated at the other end.