Use the Separation of Bearer and Signaling feature to reduce the costs of private leased lines. The Separation of Bearer and Signaling (SBS) feature provides a feature set similar to Distributed Communications Service Plus (DCS+). The SBS feature uses the Public Switched Telephone Network (PSTN) for bearer (voice) element, and QSIG private network signaling over a low-cost IP Network for the signaling element of calls. SBS is available only with Communication Manager.