3Com DIGITAL MODEM Protocol Support

Protocol Support 2-19

Protocol Support

Async-Sync PPP Conversion

One of the most unique and powerful features of the

3Com Impact digital modem is its ability to convert

asynchronous Point-to-Point Protocol (PPP) into synchronous

(HDLC-based) PPP that can be transported in ISDN

B channels to communications servers and routers that have

integrated ISDN Basic Rate (BRI), Primary Rate (PRI), or

T1 access lines.

A wide variety of software and internetworking products has

been tested for interoperability with the 3Com Impact

digital modem’s Async-Sync PPPä conversion software.

QuickSelect

The 3Com Impact digital modem supports V.120 and

Async-Sync PPP conversion. The digital modem uses a

technique called QuickSelectä so that you do not have to

manually select the proper protocol for each ISDN call. With

QuickSelect enabled (the default), the digital modem

automatically detects and uses the required protocol.

Contents

Main 3Com Corporation 95052-8145 Santa Clara, California 5400 Bayfront Plaza C ONTENTS 3 A C B F IGURES T ABLES A How to Use This Guide Introduction UIDE Conventions Table 1 and Table 2 list text and icon conventions that are used throughout this guide: I NTRODUCTION Page 3Com Impact Digital Modem Features Data Capabilities Voice Capabilities Simultaneous Data and Voice Capabilities Analog Modem Capabilities 3Com Impact Digital Modem Package Contents Standard Package Contents Additional Contents ISDN Digital Line Conguration Requirements Computer System Requirements IBM PC or Compatible Requirements Apple Macintosh Requirements Cabling Requirements 2 C THE DIGITAL MODEM Page Installing the 3Com Impact Digital Modem Installing the Digital Modem in an IBM-compatible PC Page Page Conguring the 3Com Impact Digital Modem Conguration for IBM PC or Compatible Computer Page Page Page Page Page Conguration for Apple Macintosh Computer Page Placing and Receiving Calls Placing ISDN Data Calls Multilink PPP Calls With Dynamic Bandwidth Allocation Page Placing Analog Modem Calls Using Communications Software to Place Calls Receiving Data Calls Using the Phone Out Port Placing Calls Using the Phone Out Port Receiving Calls Using the Phone Out Port Protocol Support Async-Sync PPP Conversion QuickSelect 3 Troubleshooting Tips Page Page Page Downloading Firmware to Your External Digital Modem Page A O Page B REGISTERS, AND RESULT C AT Command Set for the 3Com Impact Digital Modem Table B-1 summarizes the AT command set. Page Page AT Command Set for Internal Analog Fax Modem Table B-1 summarizes the AT command set for the internal analog modem. Page Page Remote S Registers Page Page Digital Modem Result Codes Table B-4 lists the 3Com Impact digital modem result codes. C On-line Technical Services 3Com Bulletin Board Service World Wide Web Site Ask3Com on CompuServe 3ComFacts Automated Fax Service Support from Your Network Supplier Support from 3Com Returning Products for Repair