A service destination point (SDP) acts as a logical way of directing traffic from one 7705 SAR router to another through a unidirectional (one-way) service tunnel. The SDP terminates at the far-end 7705 SAR router, which directs packets to the correct service egress service access point (SAP) on that device. All services mapped to an SDP use the GRE, IP, or MPLS transport encapsulation type.
For information about service transport tunnels, see the 7705 SAR Services Guide. Service transport tunnels can support up to eight forwarding classes and can be used by multiple services.