Source traffic smoothing and ATM network interfaces for VBR MPEG video encoders

Abstract

This paper describes approaches for shaping and smoothing traffic from VBR MPEG video encoders and interfacing to ATM networks, by introducing delay and rate buffering between the video encoding and decoding processes, and by flow controlling the data rate out of the encoder buffer into the network. Three algorithms for flow control are defined and compared in terms of their resulting traffic profile. The performance of these algorithms in the presence of a leaky bucket ATM network access controller is studied. The relationship between the leaky bucket algorithm parameters and VBR MPEG encoder parameters is discussed. It is shown that significant gains in performance can be obtained by appropriate selection of traffic smoothing algorithms at the output of a VBR MPEG encoder.