Preemptive Priority Mechanism Research Articles

An adaptive bandwidth allocation scheme with preemptive priority for integrated voice/data mobile networks

This paper presents an adaptive bandwidth allocation scheme, called complete sharing with preemptive priority (CSPP) scheme, for integrated voice/data mobile networks. It uses the complete sharing approach to maximize the bandwidth utilization efficiency by allowing data traffic to share all the bandwidth resource of a cell and introduces a preemptive priority mechanism to maintain the high performance of voice traffic while the injury of data traffic is compensated through a victim buffer. A degradation/compensation mechanism is applied to the data traffic which has elastic characteristics. The model of the CSPP scheme is analyzed by a two dimensional Markov process. The steady state probability vector is obtained recursively by the matrix-analytic method and many important performance measures are then determined such as different types of probabilities, total channel utilization, transmission delay, busy period time and blocking period time. From the performance analysis and comparison as well as the numerical results, we can conclude that the CSPP scheme can achieve complete service differentiation for different traffic classes and very high and stable channel utilization under various traffic loads. By adjusting the defined constraint factors, we can not only maintain higher priority for handoff voice over new voice calls and voice calls over data calls but also provide necessary protection for data calls in hot-spot data traffic situations

An adaptive bandwidth allocation scheme with preemptive priority for integrated voice/data mobile networks

This paper presents an adaptive bandwidth allocation scheme, called complete sharing with preemptive priority (CSPP) scheme, for integrated voice/data mobile networks. It uses the complete sharing approach to maximize the bandwidth utilization efficiency by allowing data traffic to share all the bandwidth resource of a cell and introduces a preemptive priority mechanism to maintain the high performance of voice traffic while the injury of data traffic is compensated through a victim buffer. A degradation/compensation mechanism is applied to the data traffic which has elastic characteristics. The model of the CSPP scheme is analyzed by a two dimensional Markov process. The steady state probability vector is obtained recursively by the matrix-analytic method and many important performance measures are then determined such as different types of probabilities, total channel utilization, transmission delay, busy period time and blocking period time. From the performance analysis and comparison as well as the numerical results, we can conclude that the CSPP scheme can achieve complete service differentiation for different traffic classes and very high and stable channel utilization under various traffic loads. By adjusting the defined constraint factors, we can not only maintain higher priority for handoff voice over new voice calls and voice calls over data calls but also provide necessary protection for data calls in hot-spot data traffic situations

Throughput Analysis An Input Buffered Integrated Packet Switch With Unbalanced Output Load Distributions

This paper studies the impact of unbalanced output load distribution in an input buffered integrated packet switch when a preemptive priority mechanism for service is given to real time traffic. The performance of interest here is the saturation throughput of non-real time traffic in which the formula will be derived directly from a balance case. The analysis will take into consideration the presence of the real time traffic and the switch structure. A comparison will be made with the case of balanced output load. We have found that the unbalanced output load distribution in the presence of real-time traffic reduces the saturation throughput of the non-real time traffic significantly for this switch structure. Keywords: Integrated Packet Switch,Queueing Theory