This document provides a sample configuration for a VG248 port to
deliver the proper signal to light the MWI on a Caller ID box connected to an
Ensure that Cisco CallManager is integrated with your voice mail system
before you attempt this configuration.
The information in this document is based on these software and
The information in this document was created from the devices in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.
Technical Tips Conventions for more information on document
The VG248 Gateway is a product enabled by Cisco AVVID (Architecture for
Video, Voice, and Integrated Data) that permits organizations to continue using
their analog devices with the current IP Telephony technology. The VG248 is a
gateway for using analog phones, fax machines, modems, voice mail systems, and
speakerphones within an organization voice system based on Cisco CallManager.
With a system of analog phones connected inline with Caller ID boxes
that have Message Waiting Indicators (MWI), it has to be assured that the
Caller ID boxes receive the proper signal from the telephone company to
successfully light the MWI, which indicates that there is a voice mail waiting.
The two types of signals that are propagated by telephone companies are
Stutter Tones and Frequency-Shift Keying (FSK)
Tones. Even though the purpose of these tones is to turn the MWI on
when a message is recorded, they do not work for all the Caller ID box models
that are provided by telephone companies.
Note: The power consumed by the VG248 ranges from 50W to 160W, which
depends on the status of the phones connected to it.
The VG248 supports different methods for sending MWI messages to analog
phones. Because you might have different types of analog phones connected to
the VG248, you can modify the MWI type on a per-port basis. So, if you have
analog phones that contain MWI lamps, then you can notify users of awaiting
messages using the MWI lamp. Or, you can choose to play a tone when users pick
up their phones.
These are the methods supported by the VG248:
Lamp (90-Volt Signal)—Illuminates the lamp on the
Caller ID (FSK Tone)—Uses the caller ID mechanism to
send MWI messages to the LCD screen on the phone.
Stutter (Stutter Tone)—Plays tones when the user
picks up the phone.
Lamp + Stutter—Illuminates the lamp and plays a
Caller ID + Stutter—Sends a message to the LCD
screen and plays a tone.
None—Does not send MWI
Complete these steps in order to configure the VG248 port to support
Caller ID (FSK Tone) on a Caller ID box inline with an analog
From the Main menu, choose
Choose Port specific
Use the arrow keys to select the port to configure and press
Choose MWI method.
Choose the caller ID
There is currently no verification procedure available for this
This section provides information you can use to troubleshoot your
You can set the VG248 to log much more detail (information, error, or
warnings), and logging to specific ports. Complete these steps in order to set
logging levels, and select ports:
From the Main menu, choose
Choose Event log.
Choose Set logging
In the Set Logging Levels select Voice Mail (VM)
and SCCP Errors + Warnings + Info +
In the Set Logged Port, select a port on which to
Select View New from the
From the selected port, make a call to the analog phone inline with
the Caller ID box and record a message. The events display in the VG248 Telnet
session, and the MWI should light.