Connection Admission Control for Video Traffic Using Modified Equivalent Capacity, " In

in dramatically different subjective performance. These results clearly demonstrate the efficacy of this joint source-channel coding approach. VII. CONCLUSION We have presented a joint source-channel coding approach to ATM-based network transport of digital video which simultaneously maximizes the number of source streams that can be supported while minimizing the end-to-end distortion. An information-theoretic performance evaluation methodology has been provided which is useful in predicting ultimate performance bounds and as a guide in designing practical systems. This methodology clearly demonstrates the importance of proper joint selection of source and channel coding rates. We have also demonstrated an eminently practical class of joint source-channel schemes employing MPEG-2 source and RS channel codes. These practical schemes have been shown to approach the information-theoretic predictions with increasing complexity. The results presented clearly demonstrate the effectiveness of this joint source-channel coding approach. Although the primary motivation for this work has been on the use of joint source-channel coding to optimize statistical multiplexing performance, this approach also has some potential use in a call admission control scheme. More specifically, based upon knowledge of individual source traffic descriptors and the number of present users in the network, the source and channel coding rates of all users can be reallocated, if necessary , to accommodate new users while maximizing the end-to-end reconstructed video quality provided to each user. A call admission strategy based on this approach is presently under investigation. REFERENCES [1] R. Kurceren and J. W. Modestino, " Use of FEC coding to improve statistical multiplexing performance for video transport over ATM networks, " Submitted to IEEE Trans. Large deviations approximation for fluid queues fed by a large number of on/off sources, " IEEE J. A Markov modulated characterization of packetized voice and data traffic and related statistical multiplexer performance , " IEEE J. A class of data traffic processes-covariance function characterization and related queueing results, " Bell Sys. Two-state MMPP modelling of ATM su-perposed traffic streams based on the characterization of correlated in-terarrival times, " in