Detect incoming phone call and display information based on caller id

This article is a brief introduction about detecting incoming calls in call centers in relation with Ozeki VoIP SIP SDK. After reading through this page you will be fully familiar with all the essential terms concerning incoming call detection and what you will need for creating your own solution using Ozeki VoIP SIP SDK.

Caller's identification

In an ordinary telephone system the identification of the caller is based upon the phone number they use. This identification can be done in VoIP solutions too, but is usually based upon the caller's ID, that can be a SIP account, an alias or in some cases even a phone number.

The caller's identification can be implemented in many ways. In case of simple VoIP communication system, like a softphone the identification is made upon the contact information of the users. In a call center it is a bit more difficult as the customers who call the call center can use different solutions, they can even call from an ordinary telephone set through the PSTN.

Figure 1 - VoIP incoming call detection

In case of a call center the caller information can be stored in database tables, given the large number of information to be stored. This solution is the simplest and the easiest to handle as databases are designed for supporting sort and lookup methods.

When a customer calls a call center the server application can make a database query for the caller information and can decide on the next step according to the result. In some cases the call center agents can be assigned to certain customers, for example, in this case the caller can be directed to the proper agent according to the database information.

Ozeki VoIP SIP SDK provides the basic background for caller identification, you can use the provided methods to get the caller's basic data and you can use it according to your actual business logic in your call center solution.

The example program you can download from "How to create a call assistant" page. This is a basic call center solution that stores the customer data in a database and displays that data in a window when an incoming or outgoing call is made.

In this article the part of the example application will be explained that does the datasheet displaying for the incoming calls. If you want to know more about the other parts of the example program, you can find information about them in the following articles:

The example program also covers the topics of displaying customer data in case of outgoing calls, please check the above mentioned articles too to get a full picture about the example program.

Training guides, simple examples

If you would like to visit the detailed developer documentations, you can learn much more from the Ozeki VoIP SIP SDK Training chapter.


This article introduced you the basic knowledge about incoming call detection in call centers and showed how Ozeki VoIP SIP SDK can help you to fulfill your wishes about this topic. If you have read through this page carefully, you already have all the knowledge you need to start on your own solution.

As you are now familiar with all the terms concerning this topic, now it is time to take a step further and explore what other extraordinary solution Ozeki VoIP SIP SDK can provide to you.

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