Flexible wide-area group communication protocols-international experiments

In distributed applications, a group of multiple processes is required to be cooperated by exchanging multimedia data. In addition, world-wide distributed applications are being realized by using the Internet. The traditional group communication protocols assume that every pair of processes support the same and fixed delay time and reliability level. In world-wide multimedia applications, the assumption does not hold. We discuss high-speed protocols which can change the way of distributing messages to multiple destinations and retransmitting messages to processes losing the messages in the wide-area group in the change of the delay and reliability. We present the evaluation of the protocols in the world-wide environment