Multiplexing digital television sources on ATM networks

摘要

This paper investigates the transmission of digital television signals on ATM networks. The key characteristic of an ATM network is its ability of statistically multiplexing variable bit rate sources in queueing systems called multiplexers. These queues are optimally located at the output port of the switching fabrics and emptied at constant bit rate by the destined transmission links. In that framework, the paper intends to analyze the multiplexing of digital television sources which are connected at a given ATM node and share the same transmission resources. Consequently, the study starts with analyzing the packet traffic generated when pooling television sources. The paper proceeds with modeling the queue behaviors and, eventually, with deriving the multiplexing performances. These latter parameters refer to three main topics namely, the cell losses and their configurations, the transmission jitter and the statistical multiplexing. Both theoretical approaches and simulations are employed to yield the final performances. As an important issue, substantial multiplexing gains is also put into evidence through theoretical and experimental arguments. Cell loss configurations are presented to suggest what policy to implement for cell loss burst correction. It is further shown how random transmission delay and jitter turn out to be minor problems when dealing with the transmission of television services.