Pacific Bell has three ISDN Basic Rate Services to choose from: SDS ISDN, Centrex ISDN and Home ISDN. All three provide circuit switched end-to-end digital connectivity for customers at speeds up to 112 Kbps. Currently, over 80% of California has access to ISDN services.
Prices for ISDN terminal equipment have been dropping over the last year. It is currently possible to purchase a PC card, NT1 and power supply for under $500 that allows you to communicate at 112 Kbps uncompressed. Call the Pacific Bell ISDN service center at 1-800-4PB-ISDN for details on how to evaluate and purchase ISDN-related equipment. For purposes of communicating over the Internet, it will also be important to coordinate with our IP/Internet access provider.
D channel is for signaling only
Backup D channel is available in case the facility with the main signaling channel goes down.
