Integration of sensor nodes with IMS

Abstract: The number of users adopting cellular system technologies over the past years has been enormous. This rapid adoption is not comparable in any other technology. Additionally, this has meant that these users have (at least some of the time) the possibility of connectivity to others and to remote services (advanced data and voice services, such as video conferences, mobile TV, navigation, and location services). Increasingly there is no longer a clear boundary between the wide area cellular network and Internet services, as the wide area cellular network is evolving from circuit switched based technologies to an IP based system; hence these wide area cellular systems are simply becoming part of the Internet. This evolution has become a challenge for the telecommunication operators, who have been used to completely controlling their network services and billing. In an attempt to maintain this traditional role for telecommunication operators, telecommunication vendors have introduced the IP Multimedia Subsystem (IMS). A system designed to enable telecommunication operators to be able to bill the user for all of the different services accessed through the wide area cellular network. The goal of such a system is to prevent the telecommunication operators from becoming a "bit pipe" (i.e., simply providing "commodity priced" connectivity). Another relevant change that has direct impact upon this project is the role of mobile handsets as gateways between sensor networks and other networks (especially the wide area cellular networks or Internet). This has lead to integrated solutions, such as the smart house concept, mobile health monitoring, and others. This thesis project is a collaboration between Ericsson Research and SUUNTO, in which we have implemented a system for monitoring a user’s heart rate via IMS. The system (has a special focus on sports activities, but it could easily be adapted for health care) is based on internetworking sensor networks, specifically a heart rate belt that transmits data wirelessly, with the IMS network through a mobile phone or a PC. The implemented service runs on top of the SIP Presence service. This project examines two alternatives. The first is a mobile scenario, in which a person is jogging outdoors, in this setting the sensor node communicates via the person’s mobile phone, through the IMS network to a monitoring application. The second scenario is more fixed; such as a gym environment, where the sensor node communicates with a personal computer which in turn publishes the data via IMS. Once the data has been published to the Presence and group management sever, an application server subscribed to the athlete’s Presence service will be notified. The people interested in viewing this data will be able to see it through any web-browser. It will even be possible to archive, and download the data for later use by other applications. The system is not optimized yet for a truly real-time communication, as the Presence service does not offer this as other technologies (RTP, SRTP or XMPP) do. There is a big delay difference between the mobile and the fixed solution. We can say that the fixed solution is almost a real-time system for transmitting low frequency data as heart rate information. This project is a first approach to a final high performance system.