In some applications, an Ethernet interface is required to operate as a network interface and originate and terminate GRE-MPLS packets. If the application requires that GRE-MPLS packets terminate on the interface IP address instead of on the system IP address, then GRE SDP termination on the router interface IP address functionality is available. See "GRE SDP termination on router interface IP address" in the 7450 ESS, 7750 SR, 7950 XRS, and VSR Services Overview Guide.