Browsing by Author "Tang, Wen-Shiang"

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A Fuzzy Inter-Ring Route Control with PRNN Predictor Bridged Resilient Packet Rings
(2010)
Tang, Wen-Shiang
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Chang, Chung-Ju
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電機工程學系
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Department of Electrical and Computer Engineering
In this paper, we propose an intelligent inter-ring route control, called fuzzy inter-ring route control with PRNN predictor (FIRC-P), for the bridged resilient packet rings (BRPR). The FIRC-P contains three functional blocks implemented by fuzzy logic systems or pipeline recurrent neural networks (PRNN): fuzzy bridge-node congestion indicator (FBCI), PRNN downstream-node fairness predictor (PDFP), and fuzzy route controller (FRC). The determination of the FIRC-P is based on the load balancing principle, in which the CW or CCW ringlet with lower congestion degree and higher service rate will be chosen. Simulation results show that the FIRC-P improves the performance by about 10% and 220% in packet dropping probability, by about 13% and 18% in average packet delay, and by about 6% and 19% in throughput over the queue length threshold route controller (QTRC) and the shortest path route controller (SPRC), respectively.
A Wavelength Assignment and Traffic Control Scheme in Reservation Slotted OBS Rings
(2011)
Tang, Wen-Shiang
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Hsieh, Yao-Ting
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Chang, Chung-Ju
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Chung, Wen-Ching
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電子工程學系及電子研究所
In this paper, we design a slotted OBS ring with a proposed reservation signaling protocol. Also, the slotted OBS ring is designed with a wavelength assignment and traffic control (WATOR) scheme to achieve high bandwidth utilization, fairness, and stability. The WATOR scheme adopts a reservation mechanism to avoid burst collisions in the slotted OBS ring system which employs no transit buffers in each node for the reason of bypassing the traffic directly. It is sophisticatedly composed of a wavelength assigner to effectively allocate the ingress data bursts (DBs) with a wavelength and a traffic controller to determine a proper advertised fair rate. The TC further contains a local fair rate generator (LFRG) and an advertised fair rate generator (AFRG). The former generates a local fair rate not only to satisfy the ring ingress aggregated with spatial reuse (RIAS) fairness but also to diminish the effect of the propagation delay; and the latter decides the advertised fair rate referring to the local fair rate generated by the former. Simulation results show that the WA achieves system utilization higher than a group scheduling (GS) scheme [11] by about 5%, and the TC can stabilize all flows much better than but DBA [12].
An Effective Fair Bandwidth Allocation in Resilient Packet Ring
(2010)
Tang, Wen-Shiang
;
Wang, Wei-Chien
;
Chang, Chung-Ju
;
Hsieh, Yao-Ting
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電機工程學系
In this paper, we propose an effective fuzzy local fairRate generator (FLFG) for resilient packet ring (RPR) to achieve better utilization fairness and convergence time. The FLFG is composed of three components: adaptive fairRate calculator (AFC), fuzzy congestion detector (FCD), and fuzzy fairRate generator (FFG). AFC produces an estimated fairRate in the meantime FCD indicates the congestion degree of station. Finally, FFG adopts the two outputs from AFC and FCD to generate precise local fairRate. Simulation results show that FLFG performs a stable fairness algorithm and improves at least about by 200% in converge time of the fairRate over the aggressive mode (AM) and the distributed bandwidth allocation (DBA) algorithms.
An efficient algorithm to find a double-loop network that realizes a given L-shape
(2006-08-14)
Chen, Chiuyuan
;
Lan, James K.
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Tang, Wen-Shiang
;
應用數學系
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電信工程研究所
Double-loop networks have been widely studied as an architecture for local area networks. It is well known that the minimum distance diagram of a double-loop network yields an L-shape. Given a positive integer N, it is desirable to find a double-loop network with its diameter being the minimum among all double-loop networks with N nodes. Since the diameter of a double-loop network can be easily computed from its L-shape, one method is to start with a desirable L-shape and then find a double-loop network to realize it. This is a problem discussed by many authors [F Aguilo, M.A. Fiol, An efficient algorithm to find optimal double loop networks, Discrete Math. 138 (1995) 15-29, R.C. Chan, C.Y. Chen, ZX Hong, A simple algorithm to find the steps of double-loop networks, Discrete Appl. Math. 121 (2002) 61-72, C.Y. Chen, F.K. Hwang, The minimum distance diagram of double-loop networks, IEEE Trans. Comput. 49 (2000) 977-979, P. Esque, F Aguilo, M.A. Fiol, Double commutative-step diagraphs with minimum diameters, Discrete Math. 114 (1993) 147-157] and it has been open for a long time whether this problem can be solved in O(log N) time. In this paper, we will provide a simple and efficient 0 (log N)-time algorithm for solving this problem. (C) 2006 Elsevier B.V. All rights reserved.
Burst priority scheduling with FDL reassignment in optical burst switch network
(2006)
Tang, Wen-Shiang
;
Chang, Chung-Ju
;
電信工程研究所
;
Institute of Communications Engineering
The paper proposes a new burst priority scheduling scheme with fiber delay line (FDL) reassignment (BPS-FR) for optical burst switch (OBS) network. The BPS-FR scheme allows the high-priority burst to preempt the low-priority one and further the longer high-priority bursts to preempt the shorter ones. Also it reschedules the replaced bursts, either the shorter high-priority bursts or low-priority bursts, by using FDL. Simulation results show that the BPS-FR scheme improves the average dropping probability of system (Low-priority bursts) about by 43% (75%) over the preemptive latest available unused channel with void filling scheme.
FLAG: A Fuzzy Local FairRate Generator for Resilient Packet Ring
(2010-05-01)
Tang, Wen-Shiang
;
Chang, Chung-Ju
;
Tien, Po-Long
;
Wang, Wei-Chien
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電機工程學系
A local fairRate generator using fuzzy logic and the moving average technique is proposed for the resilient packet ring (RPR). The fuzzy local fairRate generator (FLAG) is designed to achieve both low convergence time and high system throughput, besides fairness. It contains three functional blocks, an adaptive fairRate calculator (AFC) to properly preproduce a local fairRate by the moving average technique, a fuzzy congestion detector (FCD) to intelligently estimate the congestion degree of the station, and a fuzzy fairRate generator (FFG) to precisely generate the local fairRate. Simulation results show that only the FLAG can stabilize all flows in parking lot scenarios with different finite traffic demands, compared with the conventional aggressive mode (AM) and distributed bandwidth allocation (DBA) fairness algorithms. Also, it attains a convergence time lower than the AM fairness algorithm by at least 7 times and the DBA fairness algorithm by at least 2 times in parking lot scenarios with greedy traffic demands.
QoS-Promoted Dynamic Bandwidth Allocation for Ethernet Passive Optical Networks
(2008)
Tang, Wen-Shiang
;
Huang, Chin-Ya
;
Chang, Chung-Ju
;
Ren, Fang-Ching
;
交大名義發表
In this paper, we propose a QOS-promoted dynamic bandwidth allocation (Q-DBA) method to support quality-of-service (QoS) requirement services for Ethernet passive optical networks (EPON). The Q-DBA method classifies the three types of services: voice, video, and data into six priorities. It can not only satisfy QoS requirements of real-time service and but also improve the QoS or non-real-time packets, Simulation results show that the Q-DBA can fulfill the video dropping probability requirement while the conventional dynamic bandwidth allocation with multiple services (DBAM) fails. Also, the Q-DBA can achieve the fairness index of average data delay close to 1 but DBAM's fairness index of average data delay varies greatly.