Instruction manual

Page 1132 of 3156 CLASS: Visual Message Waiting Indicator
553-3001-306 Standard 10.00 January 2002
The visual indication message (an “ON/OFF” CLASS VMWI specific
message) is delivered from the Meridian 1 to the CLASS sets using
Frequency Shift Keying (FSK) signaling based on Bellcore specifications, via
a CLASS modem (CMOD) unit. The CMOD units are configured using
LD 13. Once configured, the CMOD units are shared throughout a multi-
customer Meridian 1 system. When an FSK message is presented to a CLASS
set, an available CMOD unit is automatically allocated.
After all messages are retrieved, the visual indicator is cleared. The CLASS
VMWI feature will not be able to turn off the message waiting indicator until
the CLASS set has returned to the idle state, even though all of the messages
have been retrieved by the user.
The CLASS VMWI feature supports the Bellcore Single Data Message
Format (SDMF) and Multiple Data Message Format (MDMF) messaging.
These formats are configured in the Meridian 1 database using LD 10. To use
SDMF, a Class of Service of CNUS is required. For MDMF, a Class of
Service of CNUA and/or CNAA is required.
The following description outlines the general functionality of the CLASS
VMWI feature.
The following scenarios affect the sending of an ON or OFF message
indicator to a CLASS set.
If the CLASS set is idle:
• the ON/OFF message is sent immediately to the set.
If the CLASS set is busy:
• as soon as the CLASS set becomes idle (goes on-hook), the system
immediately sends the VMWI message to the set.
If the CLASS set or CMOD unit is disabled (via LD 32 or 30), or no CMOD
unit is available:
• the CLASS VMWI feature will automatically abort the VMWI message.
The CLASS set is then checked every 10 seconds, for up to 2 1/2 hours,
until the set is detected to be idle. At that time, the system will
immediately deliver the VMWI message.