A Stochastic Approach for Resource Prediction Error and Bandwidth Wastage Evaluation in Advanced Dynamic Reservation Strategies

Many studies in literature have shown that the bandwidth of an ongoing flow can dynamically change during multimedia sessions and an efficient bandwidth prediction scheme must be employed in order to guarantee the needed Quality of Service. Many contributions in literature focused on some specific reservation schemes for cellular systems, 3G/4G/5G networks, WLAN and so on. However, few of them exploited the trade-off between resource prediction error and bandwidth wastage through a general prediction technique based on the analysis of Cell Stay Time, on the direction probabilities of hand-in and hand-out events of mobile nodes among wireless cells and on the resource over-provisioning due to the uncertain mobility patterns. Our proposed scheme is based on the stochastic computation and characterization of user movements and it is absolutely general. Two novel metrics such as prediction error e and resource wastage u are defined. Moreover, predictive reservation schemes, admission prediction and resource wastage probabilistically associated to the stochastic hand-in/hand-out movement directions are proposed, with an optimization problem for the optimal pre-reservation of bandwidth in wireless system. A threshold-based reservation scheme has been considered as a practical case and it has been evaluated in terms of reservation prediction errors and resource wastage, to prove the practical effectiveness and consistence of the defined theoretical bounds.