The SBC Core transports SIP signaling over UDP. Acceptable transport types for Ingress SIP signaling is specified on the SIP signaling port and on the SIP trunk group. The transport types used for Egress SIP signaling are specified by the SBC in its routing response, determined by the SBC on a SIP trunk basis, or queried from an external DNS server.
Ingress SIP transport type acceptance is configured on a SIP trunk group basis with specific parameters configurable on a SIP trunk basis. Egress SIP transport type is configured through the Egress IP signaling profile in the SBC or on a SIP trunk basis, or may be determined by a DNS NAPTR (Name Authority Pointer) query.