Browsing by Author "Huang, Shiang-Ming"

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A Monte Carlo Method for Estimating the Extended All-terminal Reliability
(2008)
Huang, Shiang-Ming
;
Wu, Quincy
;
Tsai, Shi-Chun
;
資訊工程學系
;
Department of Computer Science
Designing a network with optimal deployment cost and maximum reliability considerations is a hard problem, especially when the all-terminal reliability is required. For efficiently finding out an acceptable solution, Genetic Algorithms (GAs) have been widely applied to solve this problem. In these GAs, the reliability values could be calculated in their objective functions. In year 2002, an extended network reliability model was proposed which considers the connection important level between each pair of nodes. This paper proposes an approximation algorithm based on Monte Carlo simulation for the new network reliability model. This approximation algorithm can be integrated into GAs to solve the optimal cost reliable network design problem under the extended model.
ITRI-WiMAXT: A WiMAX conformance testing tool
(2010-02-01)
Lee, Hsin-Yi
;
Lin, Yi-Bing
;
Liang, Ching-Feng
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Huang, Shiang-Ming
;
資訊工程學系
The WiMAX Forum certifies and promotes the compatibility and interoperability of broadband wireless products where many testcases need to be developed for WiMAX procedures. In this paper, we develop a conformance test tool called ITRI-WiMAXT based on the TTCN-3 specifications. Then we show how WiMAX procedures are tested in ITRI-WiMAXT. Based on ITRI-WiMAXT, we have proposed several test procedures accepted by the WiMAX Forum. Copyright (C) 2009 John Wiley & Sons, Ltd.
OLM: Opportunistic Layered Multicasting for Scalable IPTV over Mobile WiMAX
(2012-03-01)
Huang, Chih-Wei
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Huang, Shiang-Ming
;
Wu, Po-Han
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Lin, Shiang-Jiun
;
Hwang, Jenq-Neng
We propose Opportunistic Layered Multicasting (OLM), a joint user scheduling and resource allocation algorithm that provides enhanced quality and efficiency for layered video multicast over Mobile WiMAX. This work is a lead off and complete synergy of layered video multicasting with opportunistic concept. The target application is characterized by groups of users acquiring popular video programs over a fading channel. To accommodate various bandwidth requirements and device capability, video streams are coded into base and enhancement layers using scalable video coding technology. Correspondingly, the optimization problems, which select the best subset of users to receive a specific video layer and assign the most appropriate modulation and coding scheme for this video layer, are specifically formulated for both video layer types. We also design fast and effective algorithms to bridge the gap between theoretical throughput capacity and implementation concerns. Thus, the basic video quality can be efficiently guaranteed to all subscribers while creating most utility out of limited resources on enhancement information. To overcome the inevitable packet loss in a multicast session, an FEC rate adaptation scheme to approach theoretical performance is also presented. Favorable performance of the proposed algorithms is demonstrated by simulations utilizing realistic Mobile WiMAX parameters.
Reducing Feedback Load of Opportunistic Multicast Scheduling over Wireless Systems
(2010-12-01)
Huang, Shiang-Ming
;
Hwang, Jenq-Neng
;
Chen, Yaw-Chung
;
資訊工程學系
;
Department of Computer Science
Opportunistic multicast scheduling (OMS) requires the subscribers to feed back their instantaneous channel conditions frequently, and the feedback load increases linearly as the number of subscribers in the system increases. In this letter, we propose a Weakly Consistent OMS scheme for feedback reduction. The contribution of the proposed scheme is twofold: 1) feedback load is reduced while the multicast throughput performance remains comparable with the case of full feedback, and 2) no precise knowledge of the wireless fading channel is required. Performance evaluation through realistic WiMAX simulations shows that our proposed scheme can significantly reduce 65% of the feedback load while achieving 98% multicast throughput performance compared with the case of full feedback.
Reducing Feedback Load of Opportunistic Multicast Scheduling over Wireless Systems
(2010-12-01)
Huang, Shiang-Ming
;
Hwang, Jenq-Neng
;
Chen, Yaw-Chung
;
資訊工程學系
;
Department of Computer Science
Opportunistic multicast scheduling (OMS) requires the subscribers to feed back their instantaneous channel conditions frequently, and the feedback load increases linearly as the number of subscribers in the system increases. In this letter, we propose a Weakly Consistent OMS scheme for feedback reduction. The contribution of the proposed scheme is twofold: 1) feedback load is reduced while the multicast throughput performance remains comparable with the case of full feedback, and 2) no precise knowledge of the wireless fading channel is required. Performance evaluation through realistic WiMAX simulations shows that our proposed scheme can significantly reduce 65% of the feedback load while achieving 98% multicast throughput performance compared with the case of full feedback.
SIP mobility and IPv4/IPv6 dual-stack supports in 3G IP multimedia subsystem
(2006-08-01)
Huang, Shiang-Ming
;
Wu, Quincy
;
Lin, Yi-Bing
;
Yeh, Che-Hua
;
資訊工程學系
In the Universal Mobile Telecommunications System (UNITS), session initiation protocol (SIP) and IPv6 are the default protocols for IP multimedia core network subsystem (IMS). However, a user equipment (UE) may not be allowed to roam or hand off from UNITS to a private-lPv4 GPRS network. In this paper, we utilize SIP mobility and an automatic IPv6 tunneling mechanism, called Teredo, to support roaming/handoff of a UE between different networks. We have developed the first non-commercial Linux-based Teredo mechanism, and compared our solution with other Teredo implementations in the public domain. Our study indicates that our solution can reduce the tunneling overhead and transmission delay over two other implementations by 44-74%. Copyright (C) 2006 John Wiley & Sons, Ltd.