A configurable multicast multimedia framework supporting adaptive QoS

Abstract

For traditional server-to-client architecture, the sender adjusts its transmission rate according to some feedback from its receiver. But in the multicast environment, feedback messages from receivers in a multicast group of indeterminate size might induce a feedback implosion problem, in which a potentially large number of feedback messages are sent almost synchronously from the group receivers back to the server. Thus, in order to support the scalability and the heterogeneity of a multicast communication environment, the number of feedback messages must be reduced and the feedback messages should be determined in an efficient and systematic way. To solve the problem of feedback implosion and provide a smooth multimedia presentation with heterogeneous QoS considerations, we propose the configurable Multicast Multiple-stream Multimedia Streaming System (M/sup 3/SS), which is composed of the client, virtual servers, and physical servers. The M/sup 3/SS specification mechanism provides that each virtual server with a local decision as to its measurement on the state of the network by adopting the proposed feedback control scheme, and sends a feedback message back to the physical server. We then propose two schemes: the dynamic feedback control and the periodic feedback control. Based on the dynamic and periodic feedback control schemes, the physical server respectively adopts the multi-rate adaptive control scheme and the average-rate adaptive control scheme to satisfy the heterogeneous network considerations and to accommodate most LAN conditions, and then can utilize the available network bandwidth as much as possible. M/sup 3/SS achieves smooth multiple-stream multimedia presentations based on the proposed QoS-considered adaptation control schemes for continuous and static media streams.