ATIS - Alliance for Telecommunications Industry Solutions
适用范围
This Technical Report addresses the effect that protection diversity routing in Synchronous Optical NETwork (SONET) rings may have on voice transmission quality. Rural rings can be several hundred miles in circumference and@ under diversity routing conditions@ additional network nodes and path length can cause a significant increase in transmission and signal processing delay. This could affect echo performance and echo canceler operation on intraLATA calls@ interLATA calls or both. Transmission delay for exchange access is treated in ANSI T1.506a[1] and ANSI T1.508.[2] Figure 1 graphically depicts the typical range of round-trip delay in exchange access networks for normal routing. Additional delay guidelines for exchange access provided on SONET rings are given in ANSI T1.508a.[3] This Technical Report supplements the information in these standards@ and includes material on intraLATA connections as well as exchange access connections. This Technical Report presents the results of analysis of the voice transmission performance of large SONET rings during temporary diversity rerouting caused by an outage on the normal route@ and provides round-trip delay guidelines for network providers@ end-users@ and network equipment designers and manufacturers.[4]@ [5]@ [6]@ [7]@ [8]@ [9] The effects of listener and talker echo on end-user perception of voice transmission quality and the effects of increased delay on echo canceler performance are discussed. Guidelines for maximum delay are given for exchange access and intraLATA connections during diversity rerouting.