3Com AccessBuilder 980/000048/001, User Manual

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Introduction
Th is chapter outlines the features and uses of the AccessBuilder 7000
Triple Modem Module when installed in the AccessBuilder 7000 Access
Concentrator chassis.
The Triple Modem Module houses three modems on a single device
module that operate independently of each other but are identical in
the features and facilities they offer. Each modem is a fully featured,
high speed device which provides reliable asynchronous and
synchronous operation over dialled or private line networks.
The high speed transfer o f up to 33.6 K bps over dialled lines is
guaranteed by using CCITT V.42bis/MNP Class 5 d ata compression and
CCITT V.42/MNP error correction. IN addition to the fast line speeds,
each modem can transfer data to the attached computer at speeds
which can vary from 300 bps to 115200 bps.
The modems are compatible with a number of dialling methods and
protocols, such as asynchronous AT commands and CCITT V.25bis
dialling, which allow you to uses the modems in a variety of
applications and environments. You can control each Triple Modem’s
configuration, dialling characteristics and diagnostic features. Five
factory set configurations, containing the most commonly-used Triple
Modem settings, are permanently stored in each Triple Modem’s
memory, providing a quick and easy method of a configuring a Triple
Modem to be compatible with asynchronous and synchronous data
environments over 2-wire or 4-wire Private lines or the PSTN.