Handling incompatibilities between services deployed on IP-based networks

The telecommunications industry has undergone major paradigm shifts in previous years. One of these is the shift from circuit-switched networks towards packet-switched networks. There is hardly any doubt that IP will be the ubiquitous transport protocol for multimedia of the future. At present, the work towards Internet telephony has attracted a lot of attention. Two standards have been developed: SIP (session initiation protocol) by the Internet Engineering Task Force (IETF) and H.323 by the International Telecommunications Union (ITU). The rapid deployment of services on top of SIP is hindered by a well known problem, feature interactions, also well known in traditional telephony networks. In this paper, the technological changes in SIP compared to the traditional telephony network are highlighted as well as the impact of the changed business environment. In a multi-service provider environment (as encouraged by a SIP environment), the feature interaction problem is regarded to be an even more pressing issue. Services of different providers from a multitude of service creators are likely to interwork. This in turn leads to the fact that the ad-hoc approaches to service interaction handling, commonly applied in the industry today, will not be sufficient any more. In this paper, a new approach addressing these changes is introduced and the results of a case study are presented.