Extending the Internet with the intelligent network capabilities

The VoIP (voice over IP) technology is dramatically challenging the position held by the PSTN/ISDN. However, in order for this technology to gain mainstream acceptance and ultimately replace the current telephone infrastructure, the VoIP networks have to offer the IN advanced services and perform the IN call control functions. In this paper, we show how the SIP (session initiation protocol) networks can support IN capabilities. Firstly, we discuss the ability of SIP, to easily instantiate intelligent services. Secondly, we give an architecture for the IN-capable SIP networks, and a mapping from the SIP call model to the IN BCSM (basic call state model).