International Journal of Wireless and Microwave Technologies (IJWMT)

IJWMT Vol. 1, No. 2, Apr. 2011

Cover page and Table of Contents: PDF (size: 117KB)

Table Of Contents

REGULAR PAPERS

Research and Design of The Firewall Penetration Technology Serving to Informati on Sharing Systems

By GAO Shou-ping WANG Lu-da

DOI: https://doi.org/10.5815/ijwmt.2011.02.01, Pub. Date: 15 Apr. 2011

In the current information sharing systems, there is a problem of firewall penetration. As for this problem and based on the existing TCP and UDP penetration schemes, we analyze all kinds of possible transmission environments in practical applications, and then present a technique of UDP coordinating with TCP to penetrate firewalls. Finally, we present the realization of this method: a network switch --XIPSwitch, which is independent from various applications. The realization method can further solve the firewall penetration problem of the internal terminals in the existing information sharing systems.

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Demand-Driven Dynamic Spectrum Allocation in Heterogeneous Cellular Networks

By Huiyue Yi Honglin Hu Jianan Liu Bin Chen Li Wang

DOI: https://doi.org/10.5815/ijwmt.2011.02.02, Pub. Date: 15 Apr. 2011

In this paper, we address the dynamic spectrum allocation problem in next generation cellular networks under the coordinated dynamic spectrum access (CDSA) model. Firstly, considering spectrum demands of base stations, we formulate spectrum allocation under physical interference models as a nonlinear optimization problem. Then, we propose a demand-driven dynamic spectrum allocation algorithm by transforming this nonlinear optimization problem into linear programming problem. The proposed algorithm first computes initial spectrum allocation and then applies iterative enhancement. Detailed simulations show that the proposed algorithm outperforms the existing algorithms in effective spectrum utilization efficiency and in average satisfaction degree.

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A Weighed Least Square TDOA Location Algorithm for TDMA Multi-target

By WANG XU HE ZI-SHU

DOI: https://doi.org/10.5815/ijwmt.2011.02.03, Pub. Date: 15 Apr. 2011

In order to improve the location precision of multiple targets in a time division multiple address (TDMA) system, a new weighed least square algorithm is presented for multi-target ranging and locating. According to the time synchronization of the TDMA system, the range difference model between multiple targets is built using the time relations among the slot signals. Thus, the range of one target can be estimated by the other one's, and a group of estimated value can be acquired for every target. Then, the weighed least square algorithm is used to estimate the range of every target. Due to the time differences of arrival (TDOA) of all targets are used in one target's location, the location precision is improved. The ambiguity and non-solution problems in the traditional TDOA location algorithm are avoided also in the presented algorithm. At the end, the simulation results illustrate the validity of the proposed algorithm.

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Research of NCS Real-time Performance with Judging Priority Based on Generalized Stability

By Hengrong LU

DOI: https://doi.org/10.5815/ijwmt.2011.02.04, Pub. Date: 15 Apr. 2011

The conceptions of generalized stability and priority judgment function of real-time node which guaranteed the generalized stability were put forward aiming at the problem of Networked Control System (NCS) real-time performance based on shared Ethernet. From the perspective of control theory and communication theory, generalized stability and priority judgment function were applied into Real-time ETHERnet (RETHER) by using real-time performance improving method of avoiding collision based on protocol in Ethernet communication protocol. Therefore, token was passed to the real-time node with highest priority and real-time data was sent, NCS real-time performance was improved. Finally, simulation results demonstrate the effectiveness of the proposed method.

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A Novel Approach to Simulate DDoS Attack

By Qing. Li LeJun CHI ZhaoXin ZHANG

DOI: https://doi.org/10.5815/ijwmt.2011.02.05, Pub. Date: 15 Apr. 2011

Due to the rapid spread of botnets, distributed denial of service attacks have become more and more frequent and fatal. In order to detect and defend DDoS attack, many researches have been done, such as using NS2 to simulate such attacks. However, the major bottlenecks in large-scale network simulation are the memory usage and simulation time. In this paper, we present a novel approach to simulate DDoS attack, called Analytical Packet Forwarding Model (APFM), which simplifies the procedure of packet forwarding based on computation. The experimental results show that our model ensures the authenticity of the overall simulation procedure and simulation results, compared to NS2. The most significant contribution of APFM is that it significantly reduced the memory usage and simulation time.

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Fast Matching Algorithm Based on Fingerprint Classification Information

By Na Li Wenbi Rao Tiecheng Xu

DOI: https://doi.org/10.5815/ijwmt.2011.02.06, Pub. Date: 15 Apr. 2011

This paper focuses on fingerprint minutia matching algorithm. A special minutia neighbor structure is proposed during the matching process in this algorithm. It can locate fingerprints using the singular from classification information. In addition, minutia structure can be used to save the time of matching minutia in a simple but effective way. Then, the matching of minutia is based on the changeable sized boundary box. At the same time, possible reference position is computed to make sure the algorithm more robust to nonlinear deformation from fingerprint images. Experimental results on Fingerprint verification competition FVC2004 databases show that this algorithm can speed up the matching of fingerprint database with a preferable performance.

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Discussion on IGMP Snooping and Its Sequence in Industrial Applicaiton

By Sheng LU Chuan WEN

DOI: https://doi.org/10.5815/ijwmt.2011.02.07, Pub. Date: 15 Apr. 2011

This paper has an introduction on a new intelligent controller for industrial Ethernet with IGMP: ICIE (Intelligent Controller for Industrial Ethernet). It proposed a new mechanism to minimize the congestion which is based on the taking an adaptive decision during transferring multicast messages. It also focuses on the sequences analysis on IGMP snooping. It has a further discussion on the steps: receiving IGMP loin message, receiving IGMP leave message, receiving IGMP query message, sending IGMP join message, sending IGMP leave message and network topology change. According to the requirement of end device ring topology, we add a DSA tagged BPDU to indict the target of packet. It is through the external devices solicitation of join messages that allow the IGMP Snooping component to correctly decipher on which ports the downstream listeners are connected.

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A Speech Enhancement Method Based on Kalman Filtering

By Chaogang Wu Bo Li Jin Zheng

DOI: https://doi.org/10.5815/ijwmt.2011.02.08, Pub. Date: 15 Apr. 2011

The enhancement of speech degraded by non-stationary interferers is a highly relevant and difficult task for many signal processing applications. In this study, we present a monaural speech enhancement method based on spectral subtraction and Kalman filtering (KF) by extracting the Liljencrants–Fant (LF) excitation during voiced speech, in which the nature of glottal flow can be maintained. Therefore, the approach could preserve the glottal pulse's nature characteristic in Kalman filtering and thus achieve significant improvements on objective quality. The quality of the enhanced speech has been evaluated by perceptual evaluation of speech quality (PESQ) score. The results indicate that the proposed algorithm could improve the output speech quality compared with the conventional KF algorithm and sub-band spectral subtraction.

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An Incentive Compatible Reputation Model for P2P Networks

By Jianli Hu Bin Zhou

DOI: https://doi.org/10.5815/ijwmt.2011.02.09, Pub. Date: 15 Apr. 2011

An important challenge regarding peer's trust assessment in peer-to-peer (P2P) networks is how to cope with such issues as the fraudulent behaviors and the dishonest feedback behaviors from malicious peers, and the issue of inactive recommendations to others. However, these issues cannot be effectively addressed by the existing solutions. Thus, an incentive compatible reputation management model for P2P networks, named ICRM, is proposed to solve them. In ICRM, the metric of time zone is used to describe the time property of the transaction experience and the recommendation. Three other metrics such as the direct trust value, the recommendation trust value and the recommendation credibility, based on the metric of time zone are applied to express accurately the final trust level of a peer. Furthermore, the participating level is introduced as the metric to identify a peer's activeness degree. Theoretical analysis and simulation experiments demonstrate that, ICRM can effectively suppress the malicious behaviors such as providing unreliable services, or giving dishonest feedbacks to others in the P2P networks. What's more, it also can incent peers to offer recommendations to others more actively.

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A Security Routing Protocol Protecting Mobile Agent Against Cluster Attack

By Wenbing Wang Zhifeng Zhang

DOI: https://doi.org/10.5815/ijwmt.2011.02.10, Pub. Date: 15 Apr. 2011

The security issue of MA(mobile agent) is concerned for a long time, Especially for attack from malicious hosts. The paper proposes a new security routing protocol whose highlight is integrating group signature into MA system. It will decrease the probability that malicious hosts cluster to skip one host deliberately, and avoid too much invalid connection to host who is offline or rejective to service. Besides, in new protocol, each host will hold less public keys of other hosts and save time on verifying MA. The last superiority of new protocol is improving the efficiency of DoS(denial of service) attacker tracing

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