4 Message Waiting Indication (MWI)

24.4063GPPMessage Waiting Indication (MWI): Protocol specificationPSTN/ISDN simulation servicesTISPANTS

4.1 Introduction

The Message Waiting Indication (MWI) service enables the network, upon the request of a controlling user to indicate to the receiving user, that there is at least one message waiting.

4.2 Description

4.2.1 General description

The MWI service enables the application server to indicate to the subscriber, that there is at least one message waiting.

The indication is delivered to the subscriber’s UE after successful subscription to the Message Waiting Indication service as described in the present document.

Other modes of MWI service invocation are not applicable.

NOTE: Having received this indication, the subscriber user can subsequently access the message account, to have the deposited message delivered. The means by which the subscriber accesses and manages the message account are outside the scope of the present document.

4.3 Functional entities

4.3.1 User Equipment (UE)

The UE shall implement the MWI Subscriber User Agent role as described in clause 4.4.1.

4.3.2 Application Server (AS)

An application server shall implement the role of a MWI Notifier User Agent as described in clause 4.4.2.

Application Server can implement the role of the application server (AS) acting as terminating UA as described in ES 283 003 [2], clause 5.7.2.

Additionally an application server may implement other roles for the receipt and storage of the messages for example Web Server, Mail Transfer and Delivery Agent, Short Message Service centre, etc.

The definition of additional roles for an MWI Application Server is out of the scope for the current specification.

4.4 Roles

4.4.1 MWI Subscriber User Agent (MSUA)

A MWI Subscriber User Agent is an entity that is subscribed or requests information about status change of message account from an MWI AS.

Actions performed by a MWI Subscriber User Agent as a part of the user equipment are described in clause 4.7.2.1.

4.4.2 MWI Notifier User Agent (MNUA)

MNUA is an entity that provides information about changes in message account status to the MSUA.

Actions performed by a notifier user agent as a part of the application server are described in clause 4.7.2.5.

4.4.3 Message Account (MA)

The definition of the message account from the RFC 3842 [3] applies with following additions:

Message account retains multimedia messages (e.g. voice, video, fax) intended to a particular subscriber.

4.4.3.1 Identification of the message account for the message deposit

Since messages may be intended to the different public user identities that belong to the same subscriber, the message account may be configured to retain messages for any of the subscriber’s public user identities.

Configuration of a message account to retain messages for each public user identity, for a group of public user identities or for all of public user identities that belong to the same subscriber is subject to the operator’s policy.

4.4.3.2 Identification of the message account for the MWI subscription

For the identification of the message account by subscriptions to the MWI service either a public service identity can be assigned to the message account or any of subscriber’s public user identity can be used, subject to the operator’s policy (see examples in clause A.1.1.2).

4.5 Operational requirements

4.5.1 Provision/withdrawal

The MWI service shall be provided after prior arrangement with the service provider. The MWI service shall be withdrawn at the subscriber’s request or for administrative reasons.

Depending on the arrangement with the service provider either any of the subscriber’s public user identities or public service identity of the message account can be used to access the MWI service, see annex B.

The subscriber’s UE shall be made aware about the option used by service provider to identify access to the MWI service.

4.5.2 Requirements on the originating network side

No specific requirements are needed on the originating network side.

4.5.3 Requirements in the network

No specific requirements are needed in the network.

4.5.4 Requirements on the terminating network side

No specific requirements are needed in the network.

4.6 Coding requirements

The application/simple-message-summary MIME type used to provide Message Summary and Message Waiting Indication Information shall be coded as described in clause 5 of RFC 3842 [3].

The coding of the message types in the message-context-class values shall follow the rules defined in the specifications listed in the "reference" column of table 1.

Table 1: Coding requirements

Value

Reference

voice-message

RFC 3458 [5]

video-message

RFC 3938 [6]

fax-message

RFC 3458 [5]

pager-message

RFC 3458 [5]

multimedia-message

RFC 3458 [5]

text-message

RFC 3458 [5]

none

RFC 3458 [5]

The coding of the additional information about deposited messages in the application/simple-message-summary MIME type body shall be in alignment with the rules defined in clause 25 of RFC 3261 [11] for SIP extension-header (clause 3.5 of RFC 3842 [3]) and follow the rules defined in the specifications listed in the "reference" column of table 2.

Table 2: Additional information

Header

Description

Reference

To:

Indicates the subscriber’s public user identity used by correspondent to deposit a message.

clause 3.6.3 of RFC 2822 [7]

From:

Indicates the correspondent’s public user identity, if available.

clause 3.6.2 of RFC 2822 [7]

Subject:

Indicates the topic of the deposited message as provided by correspondent.

clause 3.6.5 of RFC 2822 [7]

Date:

Indicates the time and date information about message deposit.

clause 3.6.1 of RFC 2822 [7]

Priority:

Indicates the message priority as provided by correspondent.

RFC 2156 [8]

Message-ID:

Indicates a single unique message identity.

clause 3.6.4 of RFC 2822 [7]

Message-Context:

Indicates a type or context of message.

RFC 3458 [5]

4.7 Signalling requirements

4.7.1 Activation/deactivation

The MWI service is immediately activated after successful SUBSCRIBE request from the subscriber’s UE, see clause 4.7.2.

The MWI service is deactivated after subscription expiry or after unsuccessful attempt to deliver a notification about message waiting.

4.7.1A Registration/erasure

The MWI service requires no registration. Erasure is not applicable.

4.7.1B Interrogation

Interrogation of MWI is not applicable.

4.7.2 Invocation and operation

4.7.2.1 Actions at the UE

When the subscriber user agent intends to subscribe for status information changes of a message account, it shall generate a SUBSCRIBE request in accordance with RFC 3265 [4] and RFC 3842 [3] and in alignment with the procedures described in ES 283 003 [2].

Depending on the service provisioning the UE will address the SUBSCRIBE request either to one of the subscriber’s public user identities or to the public service identity of the message account (see clause 4.5.1).

The subscriber’s UE shall implement the "application/simple-message-summary" content type as described in RFC 3842 [3].

4.7.2.2 Actions at the P-CSCF

Procedures according to ES 283 003 [2] shall apply.

4.7.2.3 Actions at the serving S-CSCF

Procedures according to ES 283 003 [2] shall apply.

NOTE: Annex B includes an example of an IFC that can be used to invoke the MWI simulation service.

4.7.2.4 Actions at the terminating S-CSCF

This clause applies if the MWI service is addressed using public service identity, see clause 4.4.3.2.

Procedures according to ES 283 003 [2] shall apply.

4.7.2.5 Actions at the AS

When the Application Server receives a SUBSCRIBE request for the "message-summary" event package, the Application Server shall identify the message account which status information is requested (see clause 4.4.3.2), then the AS shall attempt to verify the identity of the source of the SUBSCRIBE request as described in ES 283 003 [2] clause 5.7.1.4, then perform authorization according to ES 283 003 [2] clause 5.7.1.5.

In case of successful subscription, the AS shall generate a response to the SUBSCRIBE request and notifications in accordance with RFC 3265 [4] and RFC 3842 [3].

4.7.2.6 Actions at the outgoing I-CSCF (THIG)

Procedures according to ES 283 003 [2] apply.

4.7.2.7 Actions at the incoming I-CSCF

Procedures according to ES 283 003 [2] apply.

4.7.2.8 Actions at the outgoing IBCF

Procedures according to ES 283 003 [2] apply.

4.7.2.9 Actions at the incoming IBCF

Procedures according to ES 283 003 [2] apply.

4.8 Interaction with other IMS capabilities

4.8.1 Presence

Interaction of the presence IMS capability and message waiting indication service is for further study.

4.8.2 Messaging

Interaction of messaging IMS capability and message waiting indication service is for further study.

4.9 Interaction with other services

4.9.1 Communication Hold (HOLD)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.2 Terminating Identification Presentation (TIP)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.3 Terminating Identification Restriction (TIR)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.4 Originating Identification Presentation (OIP)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.5 Originating Identification Restriction (OIR)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.6 CONFerence calling (CONF)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.7 Communication DIVersion services (CDIV)

The subscriber of the message waiting indication service receives the notifications about the change in the status of message account only from message waiting indication application server.

Communication diversion services shall not impact the processing of message waiting indication subscriptions, notifications and responses.

4.9.7.1 Communication Forwarding Unconditional (CFU)

MWI notifications shall not be affected by the communication forwarding unconditional service and always be forwarded to subscribers’ current location (if known).

4.9.7.2 Communication Forwarding Busy (CFB)

MWI notifications shall not be affected by the communication forwarding busy service and always be forwarded to subscribers’ current location (if known).

The UE will inform the AS if it will not be able to process the notification at the time.

4.9.7.3 Communication Forwarding No Reply (CFNR)

MWI notifications shall not be affected by the communication forwarding busy service and always be forwarded to subscribers’ current location (if known).

The S-CSCF will inform the AS if the UE can not be contacted at the time.

4.9.7.4 Communication Forwarding on Not Logged-in (CFNL)

MWI notifications shall not be affected by the communication forwarding busy service and always be forwarded to subscribers’ current location (if known).

The S-CSCF will inform the AS if the UE is not logged-in at the time.

4.9.7.5 Communication Deflection (CD)

MWI notifications shall not be affected by the communication deflection service. All the CSCFs and AS shall ignore the redirection information received from the UE and proceed a 3xx response as a 480 Temporarily Unavailable response.

4.9.8 Malicious Call IDentification (MCID)

No impact, i.e. neither service shall affect the operation of the other service.

4.9.9 Explicit Communication Transfer (ECT)

No impact, i.e. neither service shall affect the operation of the other service.

4.10 Interactions with other networks

Interaction with other networks is performed according to ES 283 003 [2].

4.10.1 Interworking with the PSTN/ISDN

Interworking of the SIP based MWI service with ISDN MWI service is for further study.

4.10.2 Interaction with PSTN/ISDN Emulation

Interworking of the SIP based MWI service with the emulation MWI service is for further study.

4.10.3 Interaction with external IP networks

Interaction with external IP networks are performed according to ES 283 003 [2].

4.11 Parameter values (timers)

Not applicable.

Annex A (informative):
Example signalling flows of Message Waiting Indication (MWI) service operation