Motorola 326X V.34 - Manual (Page 32)

1-8 About the Modem
A
bout the M
odem
Remote Configuration
Using the local front panel, an NMS, or local-modem AT ACU, you can configure a
remote modem. You can also read the remote modem’s status snapshots and receive
its configuration summary on a front panel or async terminal.
Error Correction and Data Compression
The modem provides error correction and data compression in accordance with
the V.42 and V.42bis ITU-TS recommendation. With V.42, modems automatically
determine whether to use Microcom Networking Protocol (MNP) Level 4 or Link
Access Procedure for Modems (LAPM) for error correction. Depending on the
scheme negotiated, the modem uses MNP Level 5 or V.42bis data compression. The
SDC modem uses LAPM with a Motorola proprietary data compression technology.
Security
The modem provides access security at two levels:
• Front panel
• Modem access
Front panel security lets you password-protect a modem from access by other users.
This prevents unauthorized changes from being made to a configuration. Front panel
security does not prevent you from using the modem.
You can also screen incoming calls so that unauthorized users cannot access a
modem. This is accomplished with password and callback functions.
Appendix A explains how to configure security features.
Status Snapshots
The modem’s status snapshot feature lets you view a local or remotely controlled
modem's EIA signals and Motorola circuit quality monitoring system (CQMS)
parameters, and view a configuration summary.
CQMS parameters continuously estimate major line parameters without disrupting
data traffic. Measurement of such selections as signal-to-noise ratio and receive level
helps you to isolate causes of degraded network performance.