The SBS Extension is an extension type that is translated at each SBS Terminating Node. Each SBS Extension must be Direct Inward Dial/Direct Dial In (DID/DDI) accessible at the SBS Terminating Node it is administered on. However, if the bearer call arrives at the SBS Terminating Node through other than PSTN DID/DDI trunks, for example private Tie Trunks, the SBS feature does not require that the SBS Terminating Node have physical DID/DDI trunks. You must allocate sufficient SBS Extensions for the expected SBS traffic volume.

The SBS Extension type emulates a station with three call appearances. You cannot assign a coverage path or station hunting for an SBS Extension.