3Com DIGITAL MODEM User Manual

Contents

1-4 CHAPTER 1: INTRODUCTIONData CapabilitiesThe 3Com Impact digital modem allows transmission ofasynchronous data at speeds of up to 115.2 Kbps over digitalISDN connections with the highest reliability and error-freeperformance possible. With Multilink PPP, a digital connectionof up to 128 Kbps can be established by aggregating the two56 Kbps or 64 Kbps ISDN B channels. Note that the COM portspeed of your PC limits the maximum data transmission rate tono more than 115.2 Kbps.ISDN technology reduces call setup times by more than 50%compared to V. fast/V.34 analog modem setup times,reducing the time it takes to establish a connection to underthree seconds.This high-speed performance allows you to do the following:n Dial up the Internet at high data ratesn Access your office’s LANn Access and download graphics, software, and data files morequicklyVoice CapabilitiesThe 3Com Impact digital modem’s Phone Out port allows theuse of existing analog telephone equipment (touch-tonetelephones, cordless telephones, and fax and answeringmachines) to place and receive calls over the ISDN line. Whenyou connect to another ISDN line, setup times are reduced,and voice quality is excellent.Simultaneous Data and Voice CapabilitiesThe 3Com Impact digital modem quickly processes data andvoice calls simultaneously. For example, you can send a fax orplace a voice telephone call while maintaining a high-speedconnection to the office LAN; you can also receive a voicetelephone call while you are connected to the Internet.