This specification describes the procedures and signaling required to support the efficient
transport of voiceband services across an ATM network between two Interworking Functions
(IWF) located respectively at a customer premises and at a service provider premises. It specifies
the use of ATM virtual circuits with AAL2 to transport bearer information and signaling. The
virtual circuits used may be PVCs, SPVCs, or SVCs. The specification supports the transport of
common channel signaling (CCS) information as well as channel associated signaling (CAS)
information.