3Com 3C63311 Reference Guide - Page 246

234 APPENDIX B: PATHBUILDER S330/S310 MODULE AND APPLICATION OVERVIEW Drop-and-Insert DS0 channels can be allowed to transit the entire path, providing DS0 to DS0 connectivity between end locations. Structured DS0s can also be groomed to be combined through an ATM network, thereby allowing end-to-end DS0 switching, as shown in Figure 172. Figure 172 Structured DS0 Combining DS1 10 DS0 10 DS0 Structured DS0 Grooming DS1 Up to 24 Timeslots ATM Network PBX - Private Branch Exchange VCC - Virtual Channel Connection DS0 Signaling and Dynamic Bandwidth Allocation Structured voice DS0s allow for channel-associated signaling by providing a path for DS0 ABCD bits. (See Figure 173.) Channel-associated signaling allows telephone supervision to be signaled end-to-end. Note that structured DS1 CBR occupies only the needed bandwidth for the DS0s selected. Figure 173 Channel Associated Signaling Channel Bank DS0 ABCD Bits Channel Associated Signaling (CAS)