STUDY OF MPEG-2 VIDEO TRAFFIC IN A MULTIMEDIA LAN ATM INTERNETWORK SYSTEM/

Many recent studies have been conducted involving the transport of con stant and variable bit rate MPEG-2 video in asynchronous transfer mode (ATM) networks; however, many of these studies have considered fairly homogeneous scenarios in which the only other traffic present in the ATM network, if any, are other MPEG-2 video sources, In this study the requirements of supporting MPEG-2 video communications in an ATM netw ork under unloaded and heavily loaded network conditions, in which the generated traffic sources are bursty in nature. are considered. To co mplete the study an experimental VoD testbed, developed as part of a c ollaborative research effort between the Communications Research Cente r of Canada (CRC:), Nortel and the University of Ottawa, was employed. To determine the characteristics of the MPEG-2 video traffic generate d by the VoD application in the ATM network in the presence of other t raffic, cell interarrival time measurements and cell rate snapshots at the ATM cell level were considered, Results obtained show that the en d-to-end flow control implemented in the application layer in the vide o-on-demand (VoD) system and the traffic controls implemented intermed iate network elements (e.g., routers, switches:) have significant impa cts on the characteristics of the MPEG-2 traffic carried in the ATM ne twork, Moreover, the impact of the intermediate network elements on th e characteristics of the MPEG-2 traffic increases with the amount of n on-MPEG-2 video traffic present in the network.