Computer Simulation Model for a Digital Communications Network Utilizing an Embedded Speech Encoding Technique.

摘要

This note describes a computer simulation of a model of a rate-adaptive packetized network, based on the assumption that users have available to them an embedded-coding type vocoder. Queues are controlled at each link by stripping off lower priority packets of the encoded speech. Three issues addressed in the simulation were: (1) The development of an adequate packet stripping strategy at each node, (2) The development of an end-to-end feedback strategy that would give stable results and yield an overall higher performance than was realized in the absence of feedback, and (3) The integration of the speech packets with data packets. Conclusions are that a judiciously chosen end-to-end feedback strategy can not only improve the efficiency of the system but also alleviate the problem of sudden rate drops due to link overload. The inclusion of data traffic in the model resulted in overall higher link utilization than was realized in the absence of data. (Author)