ABSTRACT: GR-534 replaces TR-TSY-000534, Issue 2 and its Revision 1, but contains NO TECHNICAL CHANGES from that original document. It has been issued strictly to conform with the new Telcordia Technologies document format and GR process, and carries a new issue number and date.

Public Switched Digital Service (PSDS) is a circuit-switched digital transport capability that will allow the subscriber to send data at 56 kilobits/second (kb/s) over the public switched network. Two implementations of PSDS are Datapath on the DMS-100, and Circuit Switched Digital Capability (CSDC) on the DMS-100. PSDS prior to Integrated Services Digital Network (ISDN) deployment can be characterized as data transmission at 56 kb/s through the use of a specialized dialing pattern, technology-dependent terminating equipment, and digital interoffice trunks using A/B bit signaling. As ISDN is deployed, PSDS becomes 56-kb/s data transmission performed by standard terminating equipment using Signaling System No. 7 (SS7) for interoffice signaling. This GR provides generic requirements on PSDS, the network side. It does not address customer premises equipment compatibility issues. This document also contains updated text that pertains to Automatic Message Accounting (AMA) to comply with the current AMA requirements.

GR-534 replaced TR-TSY-000534 and TA-TSY-000364.