Support for voicemail notifications with SIP
When using SIP, or telephony in general you’d often have two types of voice mailboxes: local and network. Historically, the first one to become popular was that local type. You can still see in movies (and your grandma’s house) people listening to their messages from a cassette recorder. Even today, most of the modern phones also come with a digital recorder.
During the last ten years, however, the network variant of this service has been gaining popularity and is now available for most mobile and fixed phone subscriptions around the world. This was made possible by the new technologies that have become available to operators.
A very important part of a network hosted voicemail service is notifying users of new messages. Mobile operators do that with SMS messages, and SIP VoIP providers do it with … RFC 3842.
RFC 3842 allows SIP clients such as SIP Communicator to subscribe for notifications of new voicemail messages. Then, every time a voice message is recorded a notification is delivered to the client. If the client is not available at the time the message was received (which would often be the case), the notification is delivered right after you launch it again and it subscribes with the network.
In addition to implementing support for this feature in our SIP module, you would also need to add the user interface part in SIP Communicator that would display the waiting messages to users and would let them dial the number where they can hear them.
References:
A Message Summary and Message Waiting Indication Event Package for SIP
http://tools.ietf.org/html/rfc3842
SIP-Specific Event Notification
http://tools.ietf.org/html/rfc3265
Other Jitsi GSoC Projects
http://gsoc.jitsi.org
Jitsi Developer Documentation
http://www.jitsi.org/index.php/Documentation/DeveloperDocumentation
The official Jitsi website
http://www.jitsi.org