Presence service integration using interconnected IP multimedia core networks (IM-CN)

This paper describes the integration of the presence management service into existing IP Multimedia Subsystem (IMS) laboratory infrastructures. Both laboratories - NGNlab in Bratislava and the laboratory in Leipzig - use the Fraunhofer OpenIMS as core components for their testing IMS environment (i.e. Call Session Control Functions (CSCF), Home Subscriber Server (HSS)). The virtualization of these components will be described in this paper. Furthermore, the layer 3 interconnection and hence the possibility to share different applications between the locations will be discussed. The presence management service has been deployed in a state where it is ready to be used with current IMS clients, for both presence information sharing via the Session Initiation Protocol (SIP) and user authorization via Extended Markup Language (XML) Configuration Access Protocol (XCAP).