Network > GRE Tunnels Generic Routing Encapsulation (GRE) tunnel protocol is a carrier protocol that encapsulates a payload protocol. The GRE packet itself is encapsulated in a transport protocol (IPv4 or IPv6). The GRE tunnel connects two endpoints in a point-to-point, logical link between the firewall and a router (or another firewall). Palo Alto Networks firewalls support termination of a GRE tunnel. What are you looking for? See: Building blocks of a GRE tunnel GRE Tunnels How to provide interoperability with another vendor’s tunnel endpoint Select Add GRE Encapsulation when you create an IPSec tunnel. Looking for more? GRE Tunnels Parent topic Network