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1-2 CHAPTER 1: INTRODUCTION
The 3Com Impact ISDN External Digital Modem (referred to as the 3Com Impact digital modem throughout this guide) is an external,
3Com Impact
ISDN External
Digital Modem
3ComImpact
ISDN line
Public telephone
network
Analog or ISDN line
Internet
or
Analog or ISDN line
Corporate
LAN
Figure 1-1 Analog and Digital Network Access with the 3Com Impact Digital Modem
Four models of the 3Com Impact digital modem are sold in the U.S. and Canada:
■3C871 is the IBMâ or
■3C872 is the IBM or
■3C876 is the Appleâ Macintoshâ external digital modem product.
■3C877 is the Apple Macintosh external digital modem product with an internal 14.4 Kbps analog fax modem.