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Seamless handover between different access technologies is a great challenge as it needs to obey different performance of QoS and security constraints. Subscribers are becoming more demanding regarding roaming capabilities across... more
Seamless handover between different access technologies is a great challenge as it needs to obey different performance of QoS and security constraints. Subscribers are becoming more demanding regarding roaming capabilities across different networking technologies such as WiFi, WiMAX, and CDMA as they claim service continuity with QoS requirement and good security features. In this paper, a QoS based vertical handover mechanism between WiMAX and WiFi networks is proposed by applying the Signal to Interference and Noise Ratio SINR. The Media Independent Handover MIH (IEEE 802.21) protocol is adopted to assist in the handover decisions by providing a suitable platform for vertical handovers. The performance of the proposed SINR based vertical handover algorithm and RSS based vertical handover algorithm have been evaluated in terms of the maximum downlink throughputs.
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We propose the desirable features or criteria to be considered when designing routing protocols for mobile ad hoc networks (MANET). From a literature review to compare currently implemented routing protocols, we have identified the... more
We propose the desirable features or criteria to be considered when designing routing protocols for mobile ad hoc networks (MANET). From a literature review to compare currently implemented routing protocols, we have identified the important features that should be included in the routing protocol. Looking at the current implementations, each routing protocol has its own particular features or criteria of merit. The mobile ad hoc network is expected to contribute a greater mobility service that will become a high demand.
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This paper examines multicast traffic in single-hop local WDM lightwave networks based on a broadcast-and-select system. We use an approximate analytical solution and Markov model to show the effect of tuning time on system performance.... more
This paper examines multicast traffic in single-hop local WDM lightwave networks based on a broadcast-and-select system. We use an approximate analytical solution and Markov model to show the effect of tuning time on system performance. We also show the trade-off between average packet delay against number of channels and network offered load. Finally, we show the trade-off between blocking probability and network offered load.
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Many network administrators or providers are hesitant or not ready to offer the users the information of current bandwidth utilization on their Internet connection or other connection. There are many justifiable and unjustifiable reasons... more
Many network administrators or providers are hesitant or not ready to offer the users the information of current bandwidth utilization on their Internet connection or other connection. There are many justifiable and unjustifiable reasons for this. We believe in opening up the communication between the users and ourselves and also believe in honestly and accurately portraying the services we are receiving via our communication lines. This paper presents a case study on the performance analysis for State Government Telecommunication Network (Terengganu*Net) bandwidth utilizations and protocol distributions.
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... Receiver Performance Characteristics for Multicast Traffic in WDM Optical Network Rabi W.Habash', Borhanuddin Mohd. Ali2, Mohd Dani Baba', and Mohammad Ibrahim' 'Faculty of Electrical Engineering, Universiti... more
... Receiver Performance Characteristics for Multicast Traffic in WDM Optical Network Rabi W.Habash', Borhanuddin Mohd. Ali2, Mohd Dani Baba', and Mohammad Ibrahim' 'Faculty of Electrical Engineering, Universiti Tehologi Mara 40450 Shah Alam, Selangor, Malaysia ...
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The objective of this paper is to discuss on the implementation of cryptographic security algorithms for radio telemetry using the graphical programming software from National Instruments known as LabVIEW. The telemetry system consists of... more
The objective of this paper is to discuss on the implementation of cryptographic security algorithms for radio telemetry using the graphical programming software from National Instruments known as LabVIEW. The telemetry system consists of a remote telemetry station (RTS) and base telemetry station (BTS) for acquiring and monitoring environmental conditions respectively. RTS setup includes a desktop computer integrated with a data acquisition system, 1200 bps modem and GP300 Motorola walkie talkie (see Ghodgaonkar, D.K. et al., IEEE Proceedings Malaysia Section 2nd National Conference on Telecommunications Technology, p.88-93, 1998). The BTS has the same setup as the RTS except that it does not have a data acquisition system. The walkie-talkie operating frequency is 477.1 MHz with FM transmission. A combination of One Time Pad (OTP) and Caesar Cipher cryptographic algorithms are implemented in order to safeguard the information from eavesdroppers. OTP was chosen because it is suitable for low bit rate data
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ABSTRACT This paper presents the admission control mechanism which can minimise the overwhelming effect of limited radio resources as the demand for network service increases. The simulation study was conducted using NCTUns module with... more
ABSTRACT This paper presents the admission control mechanism which can minimise the overwhelming effect of limited radio resources as the demand for network service increases. The simulation study was conducted using NCTUns module with hierarchical Quality of Service (QoS) priority method. The result shows the proposed admission control mechanism is able to increase the number of subscriber being served and reduces the radio resources wastage by about 35%.
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For the past few years, wireless networks have played bigger role in connecting people. Demand for it services has increased tremendously. In order to provide better services and choices for high-speed internet access and multimedia... more
For the past few years, wireless networks have played bigger role in connecting people. Demand for it services has increased tremendously. In order to provide better services and choices for high-speed internet access and multimedia service for business and residential customer, IEEE has come out with new solution. Started on 2001, IEEE 802.16 working group was developing the IEEE 802.16 standards for wireless Metropolitan Area Networks. Their objective and forecast are to provide broadband wireless last-miles access in a Metropolitan Area Network, easy to deploy and giving high speed data rate and large covering area. To fulfil this objective, a good scheduling system can boost the performance of Wireless network. In this work, a detailed simulation study from the Base Station to Subscriber station (downlink) is carried out for comparing 2 different schedulers in terms of their performance. The simulation is carried out via the NCTUns simulator.
This paper presents the performance analysis of various relay stations in IEEE 802.16j Mobile Multi-hop Relay (MMR) WiMAX for half and full duplex communication. The main function of Relay Station (RS) is to enhance the network capacity... more
This paper presents the performance analysis of various relay stations in IEEE 802.16j Mobile Multi-hop Relay (MMR) WiMAX for half and full duplex communication. The main function of Relay Station (RS) is to enhance the network capacity and extends the coverage area. The efficiency of RS is evaluated based on the throughput for downlink and uplink transmission.
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This paper presents an evaluation of whether the indoor signal strength for commercial buildings fulfills the cell planning requirement. In order to provide high quality cellular service, it is necessary to place an array of distributed... more
This paper presents an evaluation of whether the indoor signal strength for commercial buildings fulfills the cell planning requirement. In order to provide high quality cellular service, it is necessary to place an array of distributed antennas connected using feeder cable within the building. With the feeder cable approach, splitters and computer software, we develop using Visual Basic 6.0. The effective radiated power (ERP) at the distributed antenna can be calculated and it can also be predicted how far the signal can go with the calculated ERP. This design process can be used to obtain an estimated indoor system requirement. All of the requirements can be achieved by applying the method in this paper.
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Research Interests:
Scheduler is one of the crucial mechanisms that influence the delivery of quality of services in WiMAX (Worldwide Interoperability for Microwave Access) networks. With the rapid advances in telecommunication technologies, Mobile Multi-hop... more
Scheduler is one of the crucial mechanisms that influence the delivery of quality of services in WiMAX (Worldwide Interoperability for Microwave Access) networks. With the rapid advances in telecommunication technologies, Mobile Multi-hop Relay (MMR) WiMAX is introduced to satisfy the ever increasing demand for higher speed and throughput. This paper discusses the scheduling technique specifically for the admission control of real-time Polling Service (rtPS). The simulation studies were conducted by adopting the weighted QoS method from the NCTUns module. The result shows the proposed admission control is capable to increase the number of subscriber being served and minimize the radio resources wastage. The capability of the admission control was also evaluated for various number of mobile stations deployed.
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Research Interests: Wireless Communications, Telecommunications, Mobile Technology, Mobile Communication, Wireless networks, and 17 moreOFDM, Performance Analysis, Wimax, Bit Error Rate, Error Correction, Throughput, Open Systems, Tcp, Packet Loss, Network Topology, Wireless communication systems, Mobile Network Technologies (WIMAX), UDP, Bandwidth, Transport Protocols, Performance Measure, and Power spectral density
The attention on WiMAX and WiFi technologies are rapidly progressing and now it is common to find them not just in laptops and personal digital assistants (PDAs), but in equipment as mobile phones, parking meters, security cameras and... more
The attention on WiMAX and WiFi technologies are rapidly progressing and now it is common to find them not just in laptops and personal digital assistants (PDAs), but in equipment as mobile phones, parking meters, security cameras and home entertainment equipment. A combination of WiFi and WiMAX deployment, will offer more cost-effective solution than a sole WiMAX or WiFi implementation. Its technology is best meets the demand for personal broadband services. This project is focused on the performance evaluation of WiMAX and WiFi systems. It is conducted using open source simulator called NCTUns 6.0. Several scenarios have been created, to evaluate the coexistence of WiMAX and WiFi technology. The data of the simulation results have been gathered and the performance with the effects of transport layer protocol, send rates, packet sizes, distances, bandwidth and queue length were analyzed. Based on the results obtained, the performance of both WiMAX and WiFi technology are not affected due to distances variation but its performance can be improved by using of other parameter such as packet size, bandwidth and queue length.
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Subscribers are becoming more demanding regarding roaming capabilities across different networking technologies such as WLAN, WiMAX, and CDMA as they claim service continuity with QoS requirement and good security features. To achieve... more
Subscribers are becoming more demanding regarding roaming capabilities across different networking technologies such as WLAN, WiMAX, and CDMA as they claim service continuity with QoS requirement and good security features. To achieve seamless handover between different access technologies is a great challenge as it needs to obey different performance of QoS and security constraints. Heterogeneous handover requires collecting network information from different entities that are not necessarily interoperable and then applying optimized policies to execute the appropriate handover decision and processing them. In this paper, a QoS based vertical handover mechanism between WiMAX and WLAN networks is proposed by applying the Signal to Interference and Noise Ratio (SINR). The Media Independent Handover (MIH) (IEEE 802.21) protocol is adopted to assist in the handover decisions by providing a suitable platform for vertical handovers.
Research Interests:
Cell breathing technique is commonly used in cellular network such as Wide Code Division Multiple Access (WCDMA) to overcome load congestion by expanding or shrinking the cell coverage. This paper presents the study of the cell breathing... more
Cell breathing technique is commonly used in cellular network such as Wide Code Division Multiple Access (WCDMA) to overcome load congestion by expanding or shrinking the cell coverage. This paper presents the study of the cell breathing boundary of urban environment for WCDMA. The base station cell coverage may expand or shrink depending on the number of mobile station being served. The COST231 HATA model is used in this study to predict the cell coverage for urban environment. The actual received signal strength indicator (RSSI) obtained by conducting drive test measurement are compared to the received signal code power (RSCP) of the COST231 HATA propagation model. The error calculated in the measurements enables to determine the minimum discrepancy between RSSI and RSCP data. Thus the COST231 HATA model can be used to predict correctly the cell coverage for urban environment. The result also shows that during light load the cell coverage radius is 0.18 km and then decreases to 0.15 km so as to limit soft handover and hence reduces load congestion.
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In this paper, a comprehensive performance analysis for Shuffle multihop WDM network is presented. Pocus is placed on the characteristics, properties and network performance parameters. In addition, a study on the effect of channel... more
In this paper, a comprehensive performance analysis for Shuffle multihop WDM network is presented. Pocus is placed on the characteristics, properties and network performance parameters. In addition, a study on the effect of channel sharing to the network performance is done. By simulating the system, the optimal degree of channel sharing that maximizes the throughput is determined.
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... K. Chandran, S. Ragunatban, S. Venkatesan, Ravi Prakash, '' A Feedback Based Scheme for Improving TCP Performance in Ad Hoc Wireless Networks, 1998. Foo Cbun Choong, TCP Performance In Mobile... more
... K. Chandran, S. Ragunatban, S. Venkatesan, Ravi Prakash, '' A Feedback Based Scheme for Improving TCP Performance in Ad Hoc Wireless Networks, 1998. Foo Cbun Choong, TCP Performance In Mobile IF',ZOOO. Gavin Holland and Nitin Vaidya, Analysis of TCP ...
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In this paper, we present a method for designing a passive optical based single-hop wavelength division multiplexing multicast architecture that can achieve a scalable structure and form the basis of a wavelength efficient single-hop WDM... more
In this paper, we present a method for designing a passive optical based single-hop wavelength division multiplexing multicast architecture that can achieve a scalable structure and form the basis of a wavelength efficient single-hop WDM network. The proposed architecture minimizes the number of wavelengths required for efficient multicast service and also minimizes tunability requirement of the transceivers. The network size scalability is achieved by adding transmitters and receivers to the designated groups. We show that the proposed system can accommodate large tuning delays and keeps with suitable throughput when the number of wavelength is equal to the number of nodes. We also show that the design can lead to a scalable structure while minimizing the number of wavelengths and tunability of the transceivers required for an efficient multicast service resulting in an improved system throughput and delay performance.
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A comprehensive performance analysis for multihop WDM networks is presented. Focus is place on the characteristics, properties and a few network performance parameters. In addition, the effect of channel sharing on the network performance... more
A comprehensive performance analysis for multihop WDM networks is presented. Focus is place on the characteristics, properties and a few network performance parameters. In addition, the effect of channel sharing on the network performance is studied. From the simulation, the optimal degree of channel sharing that maximizes the throughput is determined. From the comparison of the network performance, the most effective multihop network structure is proposed.
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Abstract The main function of relay station is to enhance the network capacity and extend the coverage area. This paper analyses the performance of relay stations in IEEE 802.16 j Mobile Multi-hop Relay (MMR) WiMAX for the transparent and... more
Abstract The main function of relay station is to enhance the network capacity and extend the coverage area. This paper analyses the performance of relay stations in IEEE 802.16 j Mobile Multi-hop Relay (MMR) WiMAX for the transparent and non-transparent modes. ...
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Research Interests:
AbstractThe handover performance in mobile network is the most important factor that can influence the Quality of Service (QoS). Today many countries in the world have migrated to more advanced mobile communication system such as the... more
AbstractThe handover performance in mobile network is the most important factor that can influence the Quality of Service (QoS). Today many countries in the world have migrated to more advanced mobile communication system such as the IEEE 802.16 e mobile WiMax ...
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Research Interests:
The wireless local area network (WLAN) is becoming the new era of wireless networking technology for the user with a strong desire for new technology. The main issue is to integrate WLAN with WAN, and handover management between the... more
The wireless local area network (WLAN) is becoming the new era of wireless networking technology for the user with a strong desire for new technology. The main issue is to integrate WLAN with WAN, and handover management between the subnets of the network should be resolved. Handover within the link layer and the network layer should be smooth and seamless. There are many alternative ways and techniques to solve this problem, such as developing a new network protocol, designing a new physical layer, enhancing or creating new algorithms. We try to figure out a proposal to solve this problem. The enhancement or modified protocol has to be developed into a new model then tested in a real network situation. In actual networking, a problem may occur and that problem must be evaluated, and the enhancement and all the modified factors investigated. Performance of handover within a WLAN is important in order to get good service for VoIP, Internet gaming and other Internet services.