Video conferencing on a LAN/MAN interconnected system: QoS evaluation

Interconnecting LANs over a wide area has become a serious problem, due to the growing resource requirements induced by multimedia real time applications like video conferencing. B-ISDNs, based on ATM, will offer resources (high bandwidth) and services (guaranteed QoS) to eventually solve the problem. In this work we investigate the intermediate solution based on the connectionless service offered by MANs. This results in the definition of a simulation model of a completely connectionless packet switched network system, whose performances are carefully evaluated by considering a workload generated by real video conferencing tools. Simulation results of end to end delay, delay jitter, resources utilization are presented showing capabilities and limits of a LAN/MAN interconnected system in supporting the bursty traffic generated by tens of users distributed on different LANs. The work shows that is possible to use the traditional packet switched transport mechanism over the connectionless service to support video conference requirements with a bandwidth utilization higher than the current one obtained by bandwidth reservation techniques.