ABSTRACT: This document provides the view of Telcordia on proposed generic criteria for incorporating ATM Virtual Path (VP) functionality into SONET cross-connects. The ATM VP functionality can be incorporated into existing SONET DCS equipment, or new cross-connect equipment can be developed with this capability, including pure ATM VP Cross-Connects (VPX's) that use SONET as physical layer medium.

This GR provides a general cross-connect evolution overview, introduces functional models, discusses potential application and operations functionality, and presents a set of ATM VP level requirements for SONET ATM Cross-Connects. Early broadband ATM services may utilize existing SONET infrastructures in a Hybrid SONET/ATM network approach. In such situations, the Hybrid Cross-Connect provides a cost-effective evolution path to ATM networks. In other situations without an existing SONET infrastructure, pure ATM VP Cross-Connects may serve in network applications where only ATM traffic needs to be supported.

This third release expands on the ATM functionality of cross-connects. It introduces a modified and more precise terminology with an extensive set of definitions pertaining to SONET, ATM, and Hybrid SONET/ATM entities. It further expands on ATM VPX's with STM capabilities, various gateway cross-connects, and network traffic management.

When using GR-2891, you may need to refer to GR-253, GR-1230, GR-1248, GR-1400, GR-2996, GR-418, GR-828, GR-1110, TR-NWT-001112, GR-1244, and/or GR-2837. You may also want to refer to GR-436, TA-TSV-001294, GR-2842, GR-2869, GR-2955, GR-2980, and GR-3009, and ANSI T1.107, T1.210, T1.640, ITU-T I.630, M.3010, and Q6/13.