带比特丢弃的AAL2分组话音复接器业务模型及性能分析

Modeling and Performance Analysis of the AAL2 Packet Voice Multiplexer with Bit Dropping

AAL2主要用于在ATM虚通路上有效传输话音、传真和话带数据 ,并可利用话音压缩技术和静默检测及消除技术来提高统计复用增益 .本文分析了用服务速率随系统状态改变的M/D′/ 1/K泊松排队系统 ,为在输入端进行比特丢弃的AAL2分组话音复接器建立模型的缺陷 ,提出了话音分组到达率随系统状态改变的M′/D/ 1/K泊松排队模型 ,并进行了性能分析 .计算机仿真证实作者提出的模型是合理的 .

Asynchronous transfer mode adaptation layer type 2 has been designed for efficie nt transport of voice,fax and voiceband data over an ATM (Asynchronous Transfer Mode) virtual circuit.High statistical multiplexing gain can be achieved by appl ying suitable compression methods on voice,fax and voiceband data and using sile nce detection and elimination on voice calls.This paper analyzes the deficiencie s of the model M/D′/1/K and builds a M′/D/1/K model on the AAL2 (ATM Adaptatio n layer type2) packet voice multiplexer where M denotes the Poisson process with the state dependent average arrival rates.Its performance is also analyzed.Simu lation results show that the M′/D/1/K model works well with the AAL2 packet voi ce multiplexer with bit dropping at the input port.