HELSINKI UNIVERSITY ABSTRACT OF THE

Current mobile phones allow third-party software to be installed on them. Mobile application distribution practices have been traditionally server-based solutions. This thesis represents an alternative way of distributing applications using the mobile networks, a peer-to-peer solution. Peer-to-peer solutions are not yet fully developed in the application distribution domain, but they may offer an intuitive way of distributing peer-to-peer applications in the future. Third generation mobile networks will allow applications to communicate with each other in peer-to-peer fashion. To use this feature, peer-to-peer applications need to be installed in the mobile devices. The applications itself can be distributed using peer-to-peer connections. A demonstration environment of this peer-to-peer application distribution solution was created to show that it is technically possible to create such a system. The demonstration application distribution system was build using SIP as the signaling proto-col. The network consists of a GPRS network and a SIP server. The mobile terminals needed changes at the software level in order to enable the distribution process. An API was designed to enable Java 2 ME applications to use this distribution mechanism. The peer-to-peer distribu-tion mechanism proved to be an working alternative to the server-based ones, but it still needs some work on charging, APIs and security issues before it can be commercially exploited