Yiqiang Q. Zhao

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In this paper, we consider GI/M/c queues with two classes of vacation mechanisms: Station vacation and server vacation. In the first one, all the servers take vacation simultaneously whenever the system becomes empty, and they also return to the system at the same time, i.e., station vacation is group vacation for all servers. This phenomenon occurs in(More)
In order to provide more value-added services, the Internet needs to classify packets into flows for different treatment. This function becomes a bottleneck in the router. High performance packet classification algorithms are therefore in high demand.This paper describes a new algorithm for packet classification using the concept of independent sets. The(More)
This paper proposes a new data compression algorithm to store the routing table in a tree structure using very little memory. This data structure is tailored to a hardware design reference model presented in this paper. By exploiting the low memory access latency and high bandwidth of on-chip memory, high-speed packet forwarding can be achieved using this(More)
Abstract Define the traffic intensity as the ratio of the arrival rate to the service rate. This paper shows that the BMAP/PH/s/s+K retrial queue with PH-retrial times is ergodic if and only if its traffic intensity is less than one. The result implies that the BMAP/PH/s/s+K retrial queue with PH-retrial times and the corresponding BMAP/PH/s queue have the(More)
A geometric tail decay of the stationary distribution has been recently studied for the GI/G/1 type Markov chain with both countable level and background states. This method is essentially the matrix analytic approach, and simplicity is an obvious advantage of this method. However, so far it can be only applied to the α-positive case (or the jittered case(More)
In this paper, we consider a BMAP/G/1 retrial queue with a server subject to breakdowns and repairs, where the life time of the server is exponential and the repair time is general. We use the supplementary variable method, which combines with the matrix-analytic method and the censoring technique, to study the system. We apply the RG-factorization of a(More)
In this paper, we consider a PH/M/2 queue in which each server has its own queue and arriving customers join the shortest queue. For this model, it has been conjectured that the decay rate of the tail probabilities for the shortest queue length in the steady state is equal to the square of the decay rate for the queue length in the corresponding PH/M/2(More)
In-order delivery of packets is a key issue in data communication networks. Re-sequencing delay and re-sequencing buffer size are two important measures in design, performance and optimization. In this paper, a large deviation result is proved for the re-sequencing buffer, which is fed by <i>m</i> parallel <i>M</i>/<i>M</i>/1 queues. The result provides a(More)