Highlight - IMPP, SIMPLE and XMPP:
- The purpose of the SIMPLE working group was to extend the SIP signaling protocol in order to fulfill the model and the protocol requirements defined by the IMPP working group (RFC 2779).
- The purpose of the XMPP working group was to extend the deployed XMPP protocol, an XML streaming technology originally implemented by the Jabber open-source community, in order to be conformant to the IMPP requirements.
1). Convergent IM Overview:
IMS Convergent Instant Messaging can
- Enhance SMS, MMS, IM, Email, and PTT into services available across a range of devices and legacy interconnected domains.
- Combine text, images, video, email, voice, and presence in a single user application.
- Multiple communication mode - (1 to 1, 1 to many users)
- Federate all type of messaging system – SMS, MMS, Email and the various IM (Instant Messages) technologies and services
- Provide offline and online delivery and forward function to (Email/ SMS/ MMS/IM)
- Support Instant Messaging Clients or GW functions for (SMS/MMS), (IMPP), (SIP/SIMPLE) and (XML/XMPP) on fixed and mobile devices
- The instant message is delivered to the appropriate address of the receiver
- Forward the message to the appropriate GW
- Support multiple Ids management – having several Public Identities with subscription to only one identity
- The instant message is delivered accordingly to the Presence information of the receiver
- Support intelligent routing feature - routed to the appropriate id among multiple Ids
- Provide a Convergent Instant Messaging Solution integrated with reusable enablers of Presence Server, XDMS, etc.
- Support unified presence stored in the PS
- Provide the related Presence feature and manage their presence - Activity status, Mood sentence, Media capabilities, etc.
- Support unified contact list stored in the GLMS
- Provide the related Buddy List feature and manage their contact list - Contact management, Privacy management, etc.
- Support instant Message storage function
- Generate a conversation history
- Industry standards (3GPP, OMA, IETF, and TISPAN), open interfaces
- The instant message is formatted after the OMA specifications
2). Convergent IM – Major Functional Entity:
2.1). The IM Client shall support:
- Perform registration with the SIP/IP Core.
- This enabler requires the IM Client be authenticated to the SIP/IP Core. It is not a matter of SIP/IP Core policy.
- Allow IM session initiation, participation, and termination.
- Send and receive instant messages using URI or a Display-Name to/from peer IM Clients, or the IM Server.
- Incorporate IM configuration data downloaded by the provisioning system (e.g., over-the-air activation).
- Notify the user of an incoming message or invitation to an IM session.
- Publish IM Client service settings (e.g., incoming IM barring activation) to the IM Server.
- Interact with Presence Client to handle presence information (e.g. publish presence information and subscribe to presence information).
- Issue commands (based on user requests) to instruct IM Server to start/stop IM conversation recording.
2.2). The IM Server shall support:
- Manage (send and receive) IM from users in One-to-One and many-to-many modes using either URI or a Display-Name.
- Support IM Clients using both mobile and fixed networks.
- Interoperate with remote IM systems i.e. interoperate with IM systems residing in other networks using reference points IM-2 and IM-8.
- In the case of session based messaging, act as conference focus and maintain public and private chat rooms [MSRP-CHAT].
- In the case of session based messaging, act as an MSRP switch including the replication of messages within chat rooms [MSRP].
- Provide online delivery of message.
- Store messages for offline users.
- Handle functionality for deferred message delivery for offline users and later retrieval.
- Use IM XDMS for IM related policies and rules (such as block lists).
- Support receiving and maintaining IM Client provided service settings (e.g., incoming IM barring activation).
- Be able to send System Messages.
- Use information stored at Shared XDMSs as input for IM Service user lists shared with other application execution.
- Store the IM conversation upon user’s request.
- Provide IM Conversation history management and retrieval functionality.
- Limit the storage size for IM conversations allocated to the IM user.
- Notify the users about the size of stored IM conversation.
- Notify the sender about the allowed maximum IM message size.
- Use presence to allow efficient delivery according to the recipient availability.
- Inform clients on message delivery.
- Update Presence information.
2.3). The IM XML Document Management Server (XDMS)
- The IM XDMS is an XCAP Server that manages XML documents (e.g.IM Conversation History and Deferred messages metadata for a user), which are specific to the IM service enabler. Management features include operations such as create, modify, retrieve, and delete.
The IM XDMS shall support to:
- Makes the link between the Instant Messaging application and the Shared-XDMS
- Provide Standard IMS SIP interfaces for interworking with any 3GPP/OMA compliant XDMS
- Perform authorization of incoming SIP and XCAP requests.
- Allow storage of descriptive information of stored IM conversations triggered by the IM server
- Checks the “Preferred Device” Presence information
- Maintain reference to the stored IM conversations, that allow these conversations to be managed (resaved, renamed, deleted, etc.).
- Manage XML documents specific to the IM service enabler.
- Accept subscriptions and notify watchers of changes to the stored IM specific documents.
- Provide Black/white List management
- Provide SMS continuity: Forward SMS to IM-to-SMS GW
- Provide Notification handling
2.4). Other XML Document Management Server (XDM) and Presence Server (PS) related entities: N/A
3). Convergent IM Architecture: (SIMPLE Reference Model)
| Interface | Between NEs | Protocol Used |
| IM-1 | IM-Client – SIP/IP-Core | SIP |
| IM-2 | IM-Server – SIP/IP-Core | SIP |
| IM-3 | IM-Server – IM XDMS | XCAP |
| IM-4 | IM-Server – Shared XDMSs | XCAP |
| IM-5 | IM XDMS – SIP/IP Core | SIP |
| IM-6 | IM XDMS – Aggregation Proxy | XCAP |
| IM-7 | IM-Client – IM-Server | MSRP |
| IM-8 | IM-Server – IM-Server | MSRP |
| IM-9 | IM-Client – Remote IM-Client | Via IM-7/IM-8 or MSRP |
| IM-10 | Shared Group XDMS – IM-Server | N/A |
| IM-11 | Shared Profile XDMS – IM-Server | N/A |
| IM-12 | IM XDMS – Search Proxy | XCAP |
