VoIP – User Friendly VOCAL User EditorKevin Brown

The Vovida Open Communication Application Library (VOCAL) is an open source project targeted at facilitating the adoption of VoIP in the marketplace. VOCAL provides the development community with software and tools needed to build new and exciting VoIP features, applications and services. VoIP is performed using the SIP protocol.

Session Initiation Protocol (SIP) is an application-layer control protocol that can establish, modify and terminate multimedia sessions or calls. SIP is only used for call setup, after which another medium (perhaps RTP) is used for the actual transfer of the voice, video, multimedia data etc.

The above diagram shows the basic SIP messages that are sent in order to set up the connection(in this case – an audio channel).

Voice over IP (VoIP) is a different approach for telephony that allows free calls to be transmitted over IP packet-switched networks(ie, the Internet). The Internet is decentralised and permits smart end-points, therefore software for implementing call control features (such as call forwarding) can be set up and controlled from anywhere on the network. This differs from the public telephone network where all call features are set up and controlled from the service providers switchboard.

VoIP allows businesses to set up and maintain their own call control features.

Internet(PSDN)

VOCAL

ProvisioningServer

Various otherservers

VOCAL`s UserEditor GUI

SIP User Agents

SIP User Agent

User Friendly User Editor

VOCAL consists of a number of servers which make up the complete system. Clients can register their SIP User Agents to VOCAL. VOCAL provides the clients with a number of call features (such as call forwarding). Each clients feature settings are held on the provisioning server, and can be changed from VOCALs user editor.To edit their settings, a client has to use either VOCALs user editor, or logon to a web site via a web browser. Both methods are clumsy and time consuming and because of this, call features are often ignored enabling important calls to be missed.

The purpose of my project is to design a user friendly interface that provides users with a fast and easy way to modify their settings. Users do not spend time sifting through menus. They want quick ‘one button’ actions.The emphasis placed on the design of the application is therefore speed of use. The application will provide all the functionality of the original VOCAL user editor.