Developing a SIP Profile Agent plug-in

A SIP Profile Agent plug-in is an ECom plug-in that provides a SIP service provider specific registration behaviour. This ECom plug-in is used by the SIP Profile server to register corresponding SIP profiles. For example, if the SIP Profile type is IETF, the profile server uses the IETF plug-in to register the profile.

The following diagram shows the relationship between a SIP Profile Agent plug-in and other components used by it:

As per the diagram above, your SIP Profile Agent plug-in must implement a few interfaces, use a few APIs and inherit a class. The following the guidelines help you in developing a SIP Profile Agent plug-in:

• Derive a profile agent plug-in class from CSIPProfileAgent, which provides an ECom interface for SIP Profile Agent plug-ins.

• You must implement the following interfaces in your plug-in class:

  • MSIPProfileAgentObserver - To receive notifications of profile registration, update and deregistration events, and any errors reported while performing these tasks.

  • MSIPProfileFSMUser - To receive profile state change notifications.

  • MSIPObserver - To receive SIP requests from the SIP connections that were not initialised by you.

  • MSIPHttpDigestChallengeObserver2 - To provide HTTP Digest authentication for SIP registrations by using an instance of the CSIPHttpDigest class.

• Apart from implementing the above listed classes and the interfaces in your plug-in class, derive and implement the following classes in your profile context and connection context classes:

  • Implement the MSIPProfileContext interface in the profile context class to get and set information about the profile while it is in a particular state.

  • Implement the MSIPConnectionObserver interface in the connection context class to receive requests, responses, connection state notifications, and error notifications from the SIP stack.

  • Implement the MSIPProxyResolverObserver interface to receive notifications about the state of the asynchronous request to resolve proxy.

  • Derive both the profile context and connection context classes from CBase to be able to create their objects on the heap.

• Create instances of the classes, CSIP and CSIPConnection and monitor the states of CSIPConnection object.

  Note: SIP Profile registration can be performed only when the state of CSIPConnection object is CSIPConnection::EActive.

• Create instance(s) of the class, CSIPRegistrationBinding to perform SIP profile registrations using the instance(s).

• Implement the SIP profile registration state machine. The state machine reacts to the state changes to CSIPConnection instances and SIP profile registrations.

For related information, see:

• SIP Profile Agent overview

• Example IETF profile agent plug-in