© 2006 Cisco Systems, Inc. All rights reserved.GWGK v Module Summary PSTN and PBX trunks are implemented using analog or digital voice interface cards. Analog trunks can be FXO, E&M, or DID and usually require voice port tuning to operate correctly. CAS trunks are created by defining DS0 groups. Digital PRI trunks use multiple time slots controlled by a signaling channel, which is referenced as a virtual voice port. QSIG trunks in Cisco Unified CallManager deployments are implemented using MGCP-controlled PRI interfaces and support supplementary features like callback and a message waiting indicator.
© 2006 Cisco Systems, Inc. All rights reserved.GWGK v2.02-2