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COMSPHERE 3900 Series Modems
Models 3920
Plus
and 3921
Plus
Firmware Update Description, Release 2.0
Document Number 3920-A2-GK43-00
April 1995
Overview
This document provides an overview of the new features in the 3920Plus and 3921Plus modems as a result of
Firmware Release 2.0. T o obtain more information about the new features, please order the new release of the
COMSPHERE 3900 Series Modems, Models 3920Plus and 3921Plus, Installation and Operation Manual
(3920-A2-GN31-10). T o order document number 3920-A2-GN31-10, please call 1-800-545-2354,
extension 2222.
Release 2.0 Feature Enhancements
• V.34 modulation
— Lease and Dial line operation.
— Data rates from 33.6K to 2400 bps with configuration capability.
• Mux enhancements
— MSD support (V.34 family, V.32 family or TMp).
— Digital Bridging function.
— Remote Digital Loopback support.
• Diagnostic T ail Circuit support – Provides the following diagnostic features over extended circuits:
— 392xPlus extension point-to-point or multipoint.
— 32 downstream devices on TMp multipoint secondary channel.
— 64 downstream devices on diagnostic channel.
— Mixed network support for 3400, 3600, and 3800 devices.
• Broadcast Download Clone over the Diagnostic Channel.
• 829 T ype Loopback – Provides support for control or tributary modems using Trellis Multipoint or
V.32 family modulations.
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• Multipoint Dial Backup Support – Provides the following enhanced PSTN backup capabilities for the
3920Plus and 3921Plus modems:
— Automatic PSTN backup upon loss of APL facility.
— Dial and Ring T one test for the PSTN facility while operating on APL.
— Testing of the APL facility before restoration to APL and disconnection from PSTN.
— Automatic or manual dial standby.
— Change, Clear, and Display call directory command.
— Subnetwork Health and Status alarms for dial backup.
• Additional VF parameter measurements with corresponding threshold alarms.
• NMS support – 6700 and 6800 Series Network Management Systems support the features described above.
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