On minimizing delay with probabilistic splitting of traffic flow in heterogeneous wireless networks

In the paper, we propose a framework to investigate how to effectively perform traffic flow splitting in heterogeneous wireless networks from a queue point. The average packet delay in heterogeneous wireless networks is derived in a probabilistic manner. The basic idea can be understood via treating the integrated heterogeneous wireless networks as different coupled and parallel queuing systems. The integrated network performance can approach that of one queue with maximal the multiplexing gain. For the purpose of illustrating the effectively of our proposed model, the Cellular/WLAN interworking is exploited. To minimize the average delay, a heuristic search algorithm is used to get the optimal probability of splitting traffic flow. Further, a Markov process is applied to evaluate the performance of the proposed scheme and compare with that of selecting the best network to access in terms of packet mean delay and blocking probability. Numerical results illustrate our proposed framework is effective and the flow splitting transmission can obtain more performance gain in heterogeneous wireless networks.