This article is a detailed guide about sending out of dialog SIP messages
in relation with Ozeki VoIP SIP SDK. After reading through this page you
will be fully familiar with all the essential terms concerning out of dialog SIP messages
and what you will need for creating your own solution using Ozeki VoIP SIP SDK.
SIP (session initiation protocol) messages are basically used for phone line establishment
by a PBX between two VoIP clients. This can be made by the provided calls of Ozeki VoIP SIP
SDK. These calls mask the actual SIP message sending and make all the background
operations that are needed for line establishment.
Figure 1 - Out of dialog SIP message
In some cases there is need for sending SIP messages that are not in connection with
the actual phone call but contain some notification or state information that can
affect the call too.
The following program code uses the background support of Ozeki VoIP SIP SDK,
therefore you will need to download and install the 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.
When using Ozeki VoIP SIP SDK you can send out of dialog SIP messages on a phone line object by
calling the SendOutofDialogInstantMessage method defined in the IPhoneLine interface (Code 1).
Code 2 - Subscribing the phone line for the event of receiving out of dialog SIP message
The actual behavior that is needed when an out of dialog SIP message is received
needs to be implemented in the phoneLine_OutofDialogInstantMessageReceived
event handler method. In this method you can define what should the program do in case of a certain
out of dialog message.
This article introduced you the basic knowledge about sending out of dialog SIP messages
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.