Advanced VoIP Call Manager

After creating a simple VoIP PBX call manager with the powerful support of Ozeki VoIP SIP SDK, you can improve your call manager to be more advanced. This article explores how you can create an advanced VoIP call manager for your SIP PBX with Ozeki SIP SDK.

Download:

08_AdvancedCallManager.zip

Please be informed that PBX development support is available in Ozeki VoIP SIP SDK from version 10.0. You can download the latest Ozeki SIP SDK version from the download page.

The Private Branch Exchange (PBX) is a hardware or software solution for communication line establishment. For this purpose Session Initiation Protocol (SIP) is used respectively. A standard PBX system can be extended with different helping tools that can be used for initiating a greater and more sophisticated communication network.

The example application introduced in this article shows an advanced call manager integrated into a PBX system. Call managing functionalities are already implemented as part of Ozeki VoIP SIP SDK, however, you can extend these functions with any further functions, by overriding some rules.

Call management can be the most difficult part of the PBX programming, as you can define very advanced rules for the call handling. This call management is the base of your PBX system logic.

The following program code uses the superb background support of Ozeki VoIP SIP SDK, therefore you will need to download and install Ozeki SIP SDK on your computer before starting to use the program code. You will also need to have Visual Studio 2010 or compatible IDE and .NET Framework installed on your system, as the program code below is written in C# language.

The example program you can download from this page shows the background call manager implementation. The main features are introduced in the following sections, and you will find some code explanations, as well.

If you have read the Basic PBX Call Manager article, you will see that a more sophisticated call manager implementation needs really advanced program designing and writing skills.

The inbuilt Call Manager implementation of Ozeki VoIP SIP SDK can handle dial plans of any difficulty level. The dial plans need a dial plan provider defined in the PBX solution that contains the routing rules.

The ringing time is also limited in this call manager solution. You can set how long you want to wait for the called extension(s) to answer the call. If the time limit is exceeded, the PBX will check the call routing rules in the dial plan and step to the next routing point.

In the PBX more extensions can register with the same SIP account. In this call manager implementation all the extensions with the same account ring when someone calls the account. The call manager uses the protocol that waits for the first acceptance of the call. When one of the extensions accepted the call, the session is initialized between the caller and that extension, and all the other extensions stop ringing.

The call manager can not only handle simple call routing rules, but it can use more difficult ones with group routing. Group routing rules can work in two ways. The group defined in a group rule consists of some extensions. These extensions can ring at the same time or in a specified order one after the other according to the group rule. This group ruling can be embedded in any levels and with them you can define really sophisticated PBX behavior.

If you have any questions or need assistance, please contact us at info@voip-sip-sdk.com

You can select a suitable Ozeki VoIP SIP SDK license for develop your PBX on Pricing and licensing information page

Related Pages

• Overview for PBX development: PBX development guides
• For the basic knowledge about integrating Ozeki VoIP SIP SDK: Quick start guide
• Download Ozeki VoIP SIP SDK form the Ozeki VoIP SIP SDK download page
• You can find licensing information of Ozeki VoIP SIP SDK on Pricing and licensing information page