Loss and delay analysis of non-Poisson M2M traffic over LTE networks

In this work, loss rate and delay of non-Poisson machine-to-machine (M2M) traffic in LTE networks have been studied. In contrast to prior works, which used Poisson process model for M2M traffic in their analysis, more realistic traffic models have been proposed, which follow the traffic patterns of M2M communications reported lately by 3GPP. A Markov-modulated Poisson process and an approximated coupled Markov-modulated Poisson process are adopted for modeling the uncoordinated and coordinated M2M network traffic, respectively. Moreover, fixed-access grant time interval algorithm is used as a low-overhead cluster–based scheduling algorithm to serve packets. Using some approximations, we first derive analytical results for the delay violation and packet loss probabilities of M2M traffic in Long-Term Evolution networks in different scenarios. We then investigate the effect of buffer size on the quality of service of M2M user equipments. Specifically, in contrast to uncoordinated traffic model, it is shown that for the coordinated traffic model increasing the buffer size above a threshold is not effective in decreasing the loss probability of user equipments. Simulation results are provided to justify the analysis and the effect of buffer size on delay and loss probabilities.