This Part is directed toward Circuit Switched Cellular Digital Packet Data (CS CDPD) Service Providers intending to build or purchase equipment for use in the CS CDPD internal network. This Part affects serving CMD-IS manufacturers, home CMD-IS and home MD-IS manufacturers, Modem Bank manufacturers and the developers of Serving Accounting Distributor, Home Accounting Distributor and Consolidation Accounting Distributor functions for the CS CDPD environment. This Part does not directly affect CS CDPD subscribers or Circuit Switched Mobile End System (CM-ES) manufacturers.