> 1 | Introduction

> Siemens GSM engines support the basic option of the multiplexer defined in the GSM 07.10 Multiplexer Protocol. The multiplexer enables one physical serial interface to be partitioned into three virtual channels. This allows you to take advantage of three simultaneous sessions running on one interface.
> Outside the GSM engine, on the application side, another multiplexer must be integrated in order to demultiplex the signal and distribute it on the three virtual channels. The external multiplexer needs to be implemented by the customer. To help system integrators save the time and expense of designing multiplexer applications, Siemens AG offers WinMux, a ready-to-use multiplex driver for Microsoft® Windows XP™ and Microsoft® Windows Vista™.
> Multiplexer protocol sources (WinMux), provided by Siemens AG, can be supplied on request. Please contact your local distributor to obtain the software and the user’s guide. For more detailed information please refer to [4].
> This document1 describes how to use the multiplexer and then explains how to design an external multiplexer and integrate it into an application on top of a Siemens GSM engine.

> 1
> The document is effective only if listed in the appropriate Release Notes as part of the technical documentation delivered with your Siemens wireless product.