An Architecture for Redundant Multicast Transmission Supporting Adaptive QoS

TitleAn Architecture for Redundant Multicast Transmission Supporting Adaptive QoS
Publication TypeConference Paper
Year of Publication2001
AuthorsBouras, C, Gkamas, A, Stamos, K, Karaliotas, A
Conference Name7th International WORKSHOP ON MULTIMEDIA SYSTEMS, Capri, Italy
Date Published7 - 9 November

In this paper we describe the architecture and the implementation of an application that was
developed for the transmission of multimedia data, using the multicast mechanism, over the
Internet. There are two major issues that have to be considered when designing and implementing
such a service, the fairness and the adaptation schemes. The fairness problem results from the fact
that receivers with different capabilities have to be served. In our application we use a mechanism
that categorizes the receivers into a number of groups according to each receiver’s capabilities and
(the mechanism) serves each group of users with a different multicast stream. With the term
“capabilities” we do not only mean the processing power of the client, but also the capacity and the
condition of the network path towards that client. Because of today’s Internet heterogeneity and the
lack of Quality of Service (QoS) support, the sender cannot assume that the receivers will
permanently be able to handle a specific bit rate. We have therefore implemented an additional
mechanism for the intra-stream bit rate adaptation.