Performability measures of the public mobile network of a tele control system

Abstract

Performability measures of the Public Mobile Network (PMN) of a Tele Control System, under prototypal development inside the EU SAFETUNNEL Project, are predicted by using stochastic models. The Tele Control System has the aim of reducing the number of accidents inside the alpine road tunnels, by implementing safety policies between Instrumented Vehicles and a Tunnel Control Centre, by means of a PMN. The use of the PMN, which supports both Global System Mobile (GSM), for voice connections, and the General Packet Radio Service (GPRS), for data connections, represents the most innovative and challenging research aspect of the system. To compute performability measures for voice and data services, we built modular sub models, hierarchically composed, by using Stochastic Activity Networks (SAN). At the first layer , we have built three sub models to compute pure unavailability and pure performance measures. Then, at the second layer, we have built two composed models. Each composed model joins the pure availability sub model and the related pure performance sub model, in order to compute perfbrmability measures, respectively for voice and data packet services. © Springer-Verlag 2004.