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What call control handling methods are available for use within my SIP application?

There are three ways of handling SIP call control within your application: -

1. The extended SIP API

The extended SIP API is very powerful and flexible.  It allows an experienced SIP programmer to gain access to SIP functionality, which would not be available to them via the generic call control API, specifically:

  • Third-party call control using re-INVITE's.
  • Fine control of SDP content in media negotiation.
  • Presentation of raw SIP messages to applications.
  • Custom headers and message bodies in the call setup INVITE.
  • Mid-call signalling, with custom headers and message bodies.
  • Unlimited sizes of data can be passed, and received as details, by the API.

Note: You can read more about the features of the extended SIP API in the 'Extended SIP API Guide' and 'SIP Programmer's Guide?.

2. The generic call control API

Access to the generic call control API is provided through use of the Media Handler Plug-in (MHP) and TiNG Resource Manager (TRM).  It acts as a wrapper around the extended SIP API, providing partial backwards compatibility with the generic call control API.

This allows customers to easily develop SIP applications that only require access to basic SIP call control functionality.


  • Does not provide the full flexibility of the Extended SIP API.
  • Does not allow you to manually assign the RTP ports used by a call.

Caution: When using this method with a Prosody X card the MHP uses the TRM to allocate TiNG resources for SIP calls.  This means the TRM must be used for resource allocation on at least one TiNG module.

3. The generic call control API with TiNG media configuration

With this method, you allocate the TiNG resources to be used by the call (Using the TiNG RTP API).  These resources are then passed into the generic call control API, when setting up calls, to be configured by the Media Handler Plug-in (MHP).

This enables you to have more control over the allocation of resources on the TiNG module, without having to configure the resources manually during call setup (codec negotiation).


  • Does not provide the full flexibility of the Extended SIP API.