This paper proposes an integrative scheme of DiffServ (differentiated service) for the IP-based network. In the scheme, QoS (Quality of Service) is ranked according to the level of both the queuing delay and the d...This paper proposes an integrative scheme of DiffServ (differentiated service) for the IP-based network. In the scheme, QoS (Quality of Service) is ranked according to the level of both the queuing delay and the drop precedence that base on the relative differentiated service; it does not take the resource reservation problem into consideration for making its implementation more simple and flexible. We will propose an implemented architecture including edge routers and core routers, and the PHB (per-hop-behavior) architecture of the routers is generalized. We adopt ERED (extended random early discard) mechanism for drop precedence and use proportional delay differentiation for queuing delay. In the proportional delay differentiation topic, we propose a new WTP (waiting time priority)-like algorithm. Besides, a new stochastic petri net model of the PHB model is given, and the performance of whole implemented PHB architecture is analyzed, too.展开更多
This paper analyzes a discrete-time multiple vacations finite-buffer queueing system with batch renewal input in which inter-arrival time of batches are arbitrarily distributed. Service and vacation times are mutually...This paper analyzes a discrete-time multiple vacations finite-buffer queueing system with batch renewal input in which inter-arrival time of batches are arbitrarily distributed. Service and vacation times are mutually independent and geometrically distributed. The server takes vacations when the system does not have any waiting jobs at a service completion epoch or a vacation completion epoch. The system is analyzed under the assumptions of late arrival system with delayed access and early arrival system. Using the supplementary variable and the imbedded Markov chain techniques, the authors obtain the queue-length distributions at pre-arrival, arbitrary and outside observer's ob- servation epochs for partial-batch rejection policy. The blocking probability of the first, an arbitrary- and the last-job in a batch have been discussed. The analysis of actual waiting-time distributions measured in slots of the first, an arbitrary- and the last-job in an accepted batch, and other performance measures along with some numerical results have also been investigated.展开更多
In recent years, the transportation system has been faced by increasing challenge in congestion and inefficiency, and research in traffic network has become a significant area of interest. In this paper, we introduce ...In recent years, the transportation system has been faced by increasing challenge in congestion and inefficiency, and research in traffic network has become a significant area of interest. In this paper, we introduce a dynamic-information-based (DIB) queueing strategy into network traffic model under the efficient routing strategy. DIB makes a packet with higher priority to be delivered if there are less packets travelling along its path from the current node to the destination. It is found that, compared with the traditional first-in-first-out (FIFO) queueing strategy, DIB can effectively bMance the traffic load of the system via delaying packets to be delivered to congested nodes. Although the network capacity has no obvious changes, some other indexes which reflect transportation efficiency are efficiently improved in the congestion state. Besides, extensive simulation results and discussions are provided to explain the phenomena. The results may provide novel insights for research on traffic systems.展开更多
文摘This paper proposes an integrative scheme of DiffServ (differentiated service) for the IP-based network. In the scheme, QoS (Quality of Service) is ranked according to the level of both the queuing delay and the drop precedence that base on the relative differentiated service; it does not take the resource reservation problem into consideration for making its implementation more simple and flexible. We will propose an implemented architecture including edge routers and core routers, and the PHB (per-hop-behavior) architecture of the routers is generalized. We adopt ERED (extended random early discard) mechanism for drop precedence and use proportional delay differentiation for queuing delay. In the proportional delay differentiation topic, we propose a new WTP (waiting time priority)-like algorithm. Besides, a new stochastic petri net model of the PHB model is given, and the performance of whole implemented PHB architecture is analyzed, too.
文摘This paper analyzes a discrete-time multiple vacations finite-buffer queueing system with batch renewal input in which inter-arrival time of batches are arbitrarily distributed. Service and vacation times are mutually independent and geometrically distributed. The server takes vacations when the system does not have any waiting jobs at a service completion epoch or a vacation completion epoch. The system is analyzed under the assumptions of late arrival system with delayed access and early arrival system. Using the supplementary variable and the imbedded Markov chain techniques, the authors obtain the queue-length distributions at pre-arrival, arbitrary and outside observer's ob- servation epochs for partial-batch rejection policy. The blocking probability of the first, an arbitrary- and the last-job in a batch have been discussed. The analysis of actual waiting-time distributions measured in slots of the first, an arbitrary- and the last-job in an accepted batch, and other performance measures along with some numerical results have also been investigated.
基金Supported by the National High Technology Research and Development Program of China under Grant No.2011AA110101the National Natural Science Foundation of China under Grant No.61201314China Scholarship Council
文摘In recent years, the transportation system has been faced by increasing challenge in congestion and inefficiency, and research in traffic network has become a significant area of interest. In this paper, we introduce a dynamic-information-based (DIB) queueing strategy into network traffic model under the efficient routing strategy. DIB makes a packet with higher priority to be delivered if there are less packets travelling along its path from the current node to the destination. It is found that, compared with the traditional first-in-first-out (FIFO) queueing strategy, DIB can effectively bMance the traffic load of the system via delaying packets to be delivered to congested nodes. Although the network capacity has no obvious changes, some other indexes which reflect transportation efficiency are efficiently improved in the congestion state. Besides, extensive simulation results and discussions are provided to explain the phenomena. The results may provide novel insights for research on traffic systems.