Introduction 1-1
This guide describes how to install and use the Model XM128U ISDN Digital Modem. It includes
a physical description and installation instructions for the hardware, as well as instructions for
installing and using FirstGear™ for configuring the modem. Use this guide as a reference for
getting started. For more detailed information about installing your Model XM128U modem, refer
to Reference Guide for the Model XM128 ISDN Digital Modem.
When used with off-the-shelf Internet or remote access client softw are, the Mo de l XM128U
modem enables mobile or home users to connect over Integrated Services Digit al Networ k (ISDN)
lines to the Internet or to branch offices. The Model XM128U m odem also all o ws a use r to c onnect
to the analog world through an analog modem, a fax machine, or a telephone.
To take advantage of constant new developments while sustaining your hardware investment, the
Model XM128U modem uses flash EPROMs that enable convenient uploadin g of newly available
firmware.
Features
The Model XM128U modem supports a variety of compression schemes including V .42bis and
Hi/fn LZS Compression (Stac). The Model XM128U modem can effectively communicat e at
speeds up to 460 kilobits per second (Kbps) over ISDN lines.
The Model XM128U modem has two analog ports to connect analog devices such as fax
machines, modems, and telephones. The Model XM128U modem can communicate over the two
B channels to different locations simultaneously, enabl ing you to send a fax and “surf” the web at
the same time. The analog ports recognize standard dual-tone multifrequency (DTMF) tones as
well as pulse dialing.
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