Using Context Information to Avoid Service Interactions in IP Telephony

Abstract

IP Telephony is an important application for building integrated communication services on IP networks. It provides telephony functionality similar to the Plain Old Telephone System. A rich variety of novel multimedia services is expected to augment the basic call functionality of IP Telephony systems. These services make the use of IP Telephony very attractive. However, multimedia services are much more complex than plain telephony services. IP-based telephony solutions are expected to be operated in a deregulated market where many different parties develop and deploy their own services. The conflicts and interactions that result from this practice make this application area challenging on a technical but also on an operational level.

The growing number of services with different quality in IP Telephony systems result in the service interaction problem, that is a well-known phenomenon in the traditional telephony system already. Existing services may interact with each other often in an undesired behavior. In this paper a rule-based approach to avoid local service interactions is proposed. The solution uses condition statements that have to be met when a service is to be executed. Current solutions consider mainly technical aspects of the end-systems or call session process as condition expressions. In the proposed approach individual user’s demands are taken into account in a novel way. This corresponds to the inherent nature of a user centric communication. Context information of the user is considered as an implicit input to the rule decision process. Additionally, a more comprehensive expressiveness of the conditions can be achieved.