scope:

Scope, Purpose and Application

This Technical Report assesses whether adequate transmission performance standards are available to allow for a timely introduction of ATM networks used to support voiceband services. It identifies transmission performance parameters required to specify ATM hardware aspects to perform the functions of digital signal processing, multiplexing, switching and transport within the Public Switched Telecommunications Network (PSTN) and other networks such as mobile networks, satellite networks, and private networks. This report was produced by T1A1.7, a working group of T1A1 which develops network transmission performance standards, and is intended to apply to Private Networks; Public Networks; and Wireless Networks.

The purpose of the report is to promote industry awareness of the need for transmission standards that are required to enable future integration of ATM as a part of the integrated network fabric. The report is also intended to assist program planners of standards bodies in developing future work plans. Manufacturers are expected to benefit from this report as it highlights those areas where industry agreements are required to support development of compatible equipment capable of operating on a national and global basis without the need for an interworking function.

The approach used in the development of this report was to identify the transmission performance parameters for which specification are required to facilitate the graceful integration of ATM technology into the digital PSTN and other networks.

In this report ATM is always assumed to be riding on a physical layer standard, e.g. SONET (Synchronous Optical NETwork) or DS3. As appropriate, the report identifies the transmission issues that must be addressed if ATM technology is to be integrated into the digital PSTN.

In today's competitive environment with the presence of many competing carriers there is difficulty in defining the term digital PSTN. To overcome this hurdle, the term Plesiochronous Digital Hierarchy/Synchronous Digital Hierarchy (PDH/SDH) oriented networks will be used, the intention being that these networks represent the byte domain while ATM networks represent the cell domain. To work between these domains, viz. between the PDH/SDH and the ATM cell domain, it is understood that an interworking function must exist and while it may physically occur in the PDH/SDH or the ATM cell-oriented hardware, it is always deemed to occur at the boundaries of the PDH/SDH and ATM cell networks.