Call Admission Control Performance Analysis in Mobile Networks Using Stochastic Well-Formed Petri Nets

(This work is an extension of our conference paper at Valuetools 2006 [18].) Stochastic Well-formed Petri Nets (SWNs) are a powerful tool for modeling complex systems with concurrency, synchronization, and cooperation. Call Admission Control (CAC) is an important mechanism for mobile networks. While several studies have been done on GSM/GPRS and on UMTS system with mixed voice and data, to the best of our knowledge, limited CAC models for mobile networks that have been proposed in the literature are represented with a unidimensional Markov chain, where the communication system was mainly based upon voice calls in order to reduce the state space of the Markov chain. Another drawback of those studies is the lack of a clear synchronization between mobile nodes and the servers. In this paper, we propose an efficient CAC scheme for mobile networks that takes into account voice connections as well as synchronous and asynchronous data connections. Furthermore, we use SWNs to model the system interaction, which consists of several mobile nodes, gateways, cells, and servers. We describe our scheme and present its analytical performance results using the WNSIM symbolic simulator of GreatSPN tool.