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Message Waiting Indication - Business V14.0

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Product Description

Message Waiting Indication -Business works in conjunction with Message Delivery Service and Message Delivery Service - Interoffice. It provides an audible or visual or audible/visual indication of messages waiting.

End-user lines may be equipped with only one of the Message Waiting Indication features. So if the end-user wants to receive both an audible and a visual message waiting indication signal, the Message Waiting Indication - Audible/Visual feature must be used to provide the service.

Message Waiting Indication - Audible (MWI-A): Provides an interrupted dial tone that is heard when the telephone receiver is lifted indicating a message or messages are waiting to be retrieved from a voice-messaging provider.

Message Waiting Indication - Visual (MWI-V): Provides a visual signal to the end-user that one or more messages are waiting to be retrieved. The end-users line must be in an "on hook" condition to receive the visual alerting signal.

Visual Message Waiting Indication requires an end-user provided visual device, such as an illuminating lamp or telephone with a visual indicator.

Message Waiting Indication - Audible/Visual (MWI-AV): Provides the end-user line with both an audible interrupted dial tone and a visual signal that one or more messages is waiting to be retrieved. The Message Waiting Indication signals are returned on the end-user's telephone line, which must be in an "on-hook" condition to receive the visual alerting signal or to deactivate the visual alerting signal.

Turning Message Waiting Indication on or off with CenturyLink Voice Messaging Service:

If Message Waiting Indication is working with CenturyLink Business Voice Messaging the end-user can turn the Message Waiting Indication indicator on or off at will by accessing their Business Voice Messaging Service mailbox, choosing Option 4 and following the voice prompts.

Turning Mwessage Waiting Indication on or off with all other voice messaging providers:

All requests to turn Message Waiting Indication features on or off are initiated by the voice messaging provider's Customer Provided Equipment (CPE) when it sends messages to the central office switch asking it to activate or deactivate the end-user's specific message waiting indication signal.

The audible signal is then initiated or turned off by the switch. For visual signals, the central office switch sends a coded burst of data in American Standard Code for Information Interchange (ASCII) format over the end-user's telephone line using FSK (Frequency Shift Key) signaling which tells the CPE device to light or to turn off.

The voice messaging provider determines how often signals will be sent to the switch to activate or deactivate the Message Waiting Indication signals sent to the end-user. Generally the provider's equipment will:

  • Initiate a request for activation of Message Waiting Indication upon receipt of the first incoming message for the end-user. The activation request is not repeated.
  • Initiate a request for deactivation of Message Waiting Indication after the end-user has accessed their voice mailbox. The provider may choose to deactivate the signal whether or not the end-user has retrieved any messages.

When a Message Waiting Indication feature is activated, it does not affect operation of the telephone line. The end-user may:

  • Call their provider to retrieve messages
  • Ignore the signal and place outgoing calls
  • Receive other incoming calls

The interrupted dial tone and/or visual signal will continue until the switch receives a request to deactivate the signal from the voice messaging provider's CPE.


Central office switches must be specially equipped to provide the various Message Waiting Indication features - Audible and/or Visual. On all new requests, contact your CenturyLink Service Manager to determine availability.

Additional information can be found in the Pre-Ordering Overview.

Compatibility & Restrictions

Feature/Service Compatible with:
Alarm Services Yes No No
Auto Call Yes Yes Yes
Business Voice Messaging Service Yes Yes Yes
Call Forwarding Yes Yes Yes
Call Transfer No No No
Call Waiting Yes Yes Yes
Centrex 21 Yes Yes No

Centrex Plus




Centrex Prime®




Centron® Yes Yes Yes
Custom Local Area Signaling Services (CLASS™) Features Yes Yes Yes
CPE * * *
Designed Services No No No
Ground Start No No No
Hunting Yes Yes Yes
Integrated Services Digital Network (ISDN) No No No
Loop Start Yes Yes Yes
One Way Only Service No No No
Party Line Service No No No
Private Line Circuit No No No
Remote Call Forward Service No No No
Telephone Answering Service No No No

* For Message Waiting Indication Audible to work, the voice messaging provider's CPE:

  • Must be programmed (by the provider) to identify their end-users equipped with a Message Waiting Indication feature.
  • Sends messages to the switch indicating that a Message Waiting Indication feature should be turned on or off on an end-user's line

* For Message Waiting Indication Visual and Message Waiting Indication Audible/Visual, a compatible visual alerting CPE device, such as an illumination lamp is required. The end-user must provide it. The CPE visual alerting device must recognize FSK signaling in order for the switch to activate or deactivate the message waiting lamp.


Rate Structure

Message Waiting Indication may have a recurring and a nonrecurring charge based on state specific Tariffs/Catalogs/Price Lists. When Message Waiting Indication and Custom Calling features are installed for the same end-user on the same line at the same time, only one nonrecurring charge should apply. When the nonrecurring charges are different amounts, the higher rate should apply.


Retail rates for this feature can be found in the state specific Tariffs/Catalogs/Price Lists.

Rates and/or discounts are available in Exhibit A or the specific rate sheet in your Interconnection or Resale Agreement.


Ordering Rules

Additional information on ordering can be found in the Ordering Overview.

Feature Activity Types (Action Codes)

The valid Feature Activity Types are:

  • D = Disconnect
  • N = Add

NOTE: When changing from one feature to another, use N and D Feature Activity Types.

Feature Codes (USOCs)

Message Waiting Indication - Audible, Visual, Audible/Visual are identified by the following USOCs:

  Message Waiting Indication - Audible Message Waiting Indication - Visual Message Waiting Indication - Audible/Visual
Centrex 21

MGN - Standard Feature

MV5 - Optional Feature

Not Available

Centrex Plus

MGN - Standard Feature

MLN - Optional Feature

Not Available

Centrex Prime

MGN - Standard Feature

MV5 - Optional Feature

Centron MWW - CenturyLink Voice Messaging Service

AWT - Non CenturyLink Voice Messaging Service


Not Available









Feature Detail (FID and Data Requirements)

Include FID TN and the 10-digit telephone number in the Feature Detail when the account is multi-line; e.g., N MWW /TN NPA-nnn-nnnn.

Adding Message Waiting Indication - Audible, Visual or Audible/Visual

This feature is ordered by including:

  • Feature Activity Type N and the appropriate USOC from the Feature Codes table.

Removing Message Waiting Indication - Audible, Visual or Audible/Visual

This feature is removed by including:

  • Feature Activity Type D and the appropriate USOC


If you are the end-user's Enhanced Service Provider (ESP) (Voice Mail Provider) as well as their Local Service Provider, and if you are using Message Delivery Service Interoffice (MDSI) Non-Hub to provision voice mail for the first time in a DMS-10 CO switch type, contact your CenturyLink Service Manager to establish a Message Desk number for the end-user's CO prior to requesting CenturyLink Message Waiting.

If you are not the end-user's ESP, the ESP will establish a Message Desk number for the end-user's CO prior to requesting CenturyLink Message Waiting or Call Forwarding features. Providing the ESP name in REMARKS, as explained below, will enable CenturyLink to determine the correct Message Desk number.

When ordering a Voice Messaging Package or Message Waiting Indicator feature in a DMS™-10 Central Office, you must provide the following information:

  • Use a manual indicator of: Y (yes)
  • Add a remark with the name of the Voice Mail Provider (even if it is CenturyLink)


The Message Service System (MSS) Field Identifier (FID) is required in 5ESS, 5RSM & 5ORM Central Office switch types if the voice messaging provider is other than CenturyLink. The following data must be entered on the service request following the MSS FID in Feature


Feature MDS MDSI
Audible-Visual *MSAAVM *MSAAVM

When removing the Message Waiting indicator in the 5ESS, 5RSM & 5ORM Central Office switch types, you must also show the removal of the MSS FID data on any additional USOCs where it appears.

Last Update: March 23, 2015