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Papers by Najwan Khambari

Research paper thumbnail of Device-To-Device Communications Direction for Disaster Management: A Review

Journal of Information System and Technology Management, Mar 12, 2024

Research paper thumbnail of Topology Influence On Tcp Congestion Control Performance In Multi-Hop Ad Hoc Wireless

Wireless ad hoc nodes are freely and dynamically self-organize in communicating with others. Each... more Wireless ad hoc nodes are freely and dynamically self-organize in communicating with others. Each node can act as host or router. However it actually depends on the capability of nodes in terms of its current power level, signal strength, number of hops, routing protocol, interference and others. In this research, a study was conducted to observe the effect of hops count over different network topologies that contribute to TCP Congestion Control performance degradation. To achieve this objective, a simulation using NS-2 with different topologies have been evaluated. The comparative analysis has been discussed based on standard observation metrics: throughput, delay and packet loss ratio. As a result, there is a relationship between types of topology and hops counts towards the performance of ad hoc network. In future, the extension study will be carried out to investigate the effect of different error rate and background traffic over same topologies.

Research paper thumbnail of QoE Enhancements for Video Traffic in Wireless Networks through Selective Packet Drops

Lecture Notes in Electrical Engineering, 2018

This paper proposes a queuing technique for important video frame packets with the objective to i... more This paper proposes a queuing technique for important video frame packets with the objective to improve the performance of video transmission as perceived by the end users, across the IEEE 802.11e network. The proposed mechanism preserves the video Quality of Experience (QoE) by avoiding the I-Frames transmitted as part of the Group of Pictures (GoP) from being dropped during queue congestion. The method is evaluated using the NS-3 simulator with the Evalvid module and the results demonstrate the video flows will have better in Mean Opinion Score from the subjective evaluation point of view compared to the original IEEE 802.11e queueing.

Research paper thumbnail of QoE Enhancements in IEEE 802.11e EDCA for Video Transmission through Selective Queueing

This paper proposes a set of performance enhancements techniques aiming to improve the perceived ... more This paper proposes a set of performance enhancements techniques aiming to improve the perceived performance of video transmission across the IEEE 802.11e network. The proposed mechanism preserves the video Quality of Experience (QoE) by protecting the I-Frames transmitted as part of the Group of Pictures (GoP) during queue congestion. The method is evaluated using the NS-3 simulator with the Evalvid module and the results demonstrate the video flows will have better Peak Signal to Noise ratio (PSNR) and less video frame drops compared to the original IEEE 802.11e queueing. Keywords—IEEE 802.11e; EDCA; QoE; NS-3; Evalvid

Research paper thumbnail of QoE-driven video enhancements in wireless networks through predictive packet drops

2017 IEEE 13th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2017

In recent years, video streaming traffic has increased exponentially over the Internet. This can ... more In recent years, video streaming traffic has increased exponentially over the Internet. This can be observed through the emergence of various video on demand sites such as Netflix, Amazon movies and others. In parallel, IEEE 802.11 (WiFi) technology has been deployed extensively from home to public areas. Although significant research has been done to address issues on video streaming through WiFi networks, it remains a challenging area. There are still interesting areas to be addressed especially to enhance user satisfaction in terms of Quality of Experience (QoE). After reviewing the existing research in improving video QoE through queuing in wireless environments, this paper propose a predictive packet drop technique to maintain a certain level of QoE based on predictive PSNR value without users' feedback. The proposed mechanism identifies packets as part of video frames and predicts the impact of their delay and loss on the resulting video performance. This reduces the need for client feedback and optimizes the resulting QoE of the delivered video. Therefore based on this information, the proposed algorithm can prioritize the video frames (I-, P- or B-Frames) whether to queue or drop in scenarios where bandwidth and limited. This method is evaluated using NS-3 simulator with Evalvid module.

Research paper thumbnail of Achieving Stable Throughput to Support QoS in IEEE 802.11 Wireless Networks

Research paper thumbnail of Improving IEEE 802.11 to Support Quality of Service in Wireless Networks

Research paper thumbnail of Improving Ieee 802.11 G Mac to Support Quality of Service for Multimedia Applications in Wireless Networks

This paper paper investigates, describes and propose better techniques to provide QoS by assignin... more This paper paper investigates, describes and propose better techniques to provide QoS by assigning new metrics to the DCF access method, involving the DCF Interframe Space (DIFS), Contention Window values and the maximum data packet size to high priority nodes, which will bias towards high priority multimedia traffic to support QoS. A simulation is done using Network Simulator 2 (NS-2) and comparisons were made between different sets of network simulation scenarios. Improvements on throughput, delay and jitter can clearly be seen and further analysis is then presented.

Research paper thumbnail of Assessing Wireless Security Implementation in Government and Private Sector Companies in Malacca–A Case Study

Research paper thumbnail of DIFS Modifications to Support QoS in IEEE 802.11 g DCF Ad-hoc Networks

Research paper thumbnail of A novel approach on teaching network security for ICT courses

2009 International Conference on Engineering Education (ICEED), 2009

This paper discusses a curriculum approach that will give emphasis on practical sessions of teach... more This paper discusses a curriculum approach that will give emphasis on practical sessions of teaching network security subjects in information and communication technology courses. As we are well aware, the need to use a practice and application oriented approach in education is paramount [1]. Research on active learning and cooperative groups showed that students grasps and have more tendency towards obtaining and realizing soft skills like leadership, communication and team work as opposed to learning using the traditional theory and exam based method. While this teaching and learning paradigm is relatively new in Malaysia, it has been practiced widely in the West. This paper examines a particular approach whereby students learning wireless security are divided into small manageable groups consisting of black hat and white hat team. The former will try to find and expose vulnerabilities in a wireless network while the latter will try to prevent such attacks on their wireless networks using hardware, software, design and enforcement of security policy and etc. This paper will try to demonstrate whether this approach will result in a more fruitful outcome in terms of students concept and theory understandings and motivation to learn.

Research paper thumbnail of Performance enhancements in IEEE 802.11 DCF MANET through variation of SIFS values in distance vector routing environment

2011 7th International Conference on Information Technology in Asia, 2011

Research paper thumbnail of Retransmission-based additional TXOP allocation for audio-video transmission by IEEE 802.11e HCCA

2011 7th International Conference on Information Technology in Asia, 2011

Abstract This paper proposed a method of allocating additional TXOP duration to replenish the ban... more Abstract This paper proposed a method of allocating additional TXOP duration to replenish the bandwidth used during the retransmission of frames at link layer in audio-video transmission by IEEE 802.11 e HCCA. In the proposed scheme, the HC monitors the ...

Research paper thumbnail of New Approach in Teaching Network Security Subjects

... Mohammad Radzi Motsidi; Mohd Fairuz Iskandar Othman; Yahaya Abd Rahim; Mohd Najwan Khambari F... more ... Mohammad Radzi Motsidi; Mohd Fairuz Iskandar Othman; Yahaya Abd Rahim; Mohd Najwan Khambari Faculty of Information and Communication Technology, Universiti Teknikal Malaysia Melaka (UTeM) Karung Berkunci 1752 ... [3] Hassan, I., Ayob, MR, Sulaiman, M., Md Tahir ...

Research paper thumbnail of Device-To-Device Communications Direction for Disaster Management: A Review

Journal of Information System and Technology Management, Mar 12, 2024

Research paper thumbnail of Topology Influence On Tcp Congestion Control Performance In Multi-Hop Ad Hoc Wireless

Wireless ad hoc nodes are freely and dynamically self-organize in communicating with others. Each... more Wireless ad hoc nodes are freely and dynamically self-organize in communicating with others. Each node can act as host or router. However it actually depends on the capability of nodes in terms of its current power level, signal strength, number of hops, routing protocol, interference and others. In this research, a study was conducted to observe the effect of hops count over different network topologies that contribute to TCP Congestion Control performance degradation. To achieve this objective, a simulation using NS-2 with different topologies have been evaluated. The comparative analysis has been discussed based on standard observation metrics: throughput, delay and packet loss ratio. As a result, there is a relationship between types of topology and hops counts towards the performance of ad hoc network. In future, the extension study will be carried out to investigate the effect of different error rate and background traffic over same topologies.

Research paper thumbnail of QoE Enhancements for Video Traffic in Wireless Networks through Selective Packet Drops

Lecture Notes in Electrical Engineering, 2018

This paper proposes a queuing technique for important video frame packets with the objective to i... more This paper proposes a queuing technique for important video frame packets with the objective to improve the performance of video transmission as perceived by the end users, across the IEEE 802.11e network. The proposed mechanism preserves the video Quality of Experience (QoE) by avoiding the I-Frames transmitted as part of the Group of Pictures (GoP) from being dropped during queue congestion. The method is evaluated using the NS-3 simulator with the Evalvid module and the results demonstrate the video flows will have better in Mean Opinion Score from the subjective evaluation point of view compared to the original IEEE 802.11e queueing.

Research paper thumbnail of QoE Enhancements in IEEE 802.11e EDCA for Video Transmission through Selective Queueing

This paper proposes a set of performance enhancements techniques aiming to improve the perceived ... more This paper proposes a set of performance enhancements techniques aiming to improve the perceived performance of video transmission across the IEEE 802.11e network. The proposed mechanism preserves the video Quality of Experience (QoE) by protecting the I-Frames transmitted as part of the Group of Pictures (GoP) during queue congestion. The method is evaluated using the NS-3 simulator with the Evalvid module and the results demonstrate the video flows will have better Peak Signal to Noise ratio (PSNR) and less video frame drops compared to the original IEEE 802.11e queueing. Keywords—IEEE 802.11e; EDCA; QoE; NS-3; Evalvid

Research paper thumbnail of QoE-driven video enhancements in wireless networks through predictive packet drops

2017 IEEE 13th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2017

In recent years, video streaming traffic has increased exponentially over the Internet. This can ... more In recent years, video streaming traffic has increased exponentially over the Internet. This can be observed through the emergence of various video on demand sites such as Netflix, Amazon movies and others. In parallel, IEEE 802.11 (WiFi) technology has been deployed extensively from home to public areas. Although significant research has been done to address issues on video streaming through WiFi networks, it remains a challenging area. There are still interesting areas to be addressed especially to enhance user satisfaction in terms of Quality of Experience (QoE). After reviewing the existing research in improving video QoE through queuing in wireless environments, this paper propose a predictive packet drop technique to maintain a certain level of QoE based on predictive PSNR value without users' feedback. The proposed mechanism identifies packets as part of video frames and predicts the impact of their delay and loss on the resulting video performance. This reduces the need for client feedback and optimizes the resulting QoE of the delivered video. Therefore based on this information, the proposed algorithm can prioritize the video frames (I-, P- or B-Frames) whether to queue or drop in scenarios where bandwidth and limited. This method is evaluated using NS-3 simulator with Evalvid module.

Research paper thumbnail of Achieving Stable Throughput to Support QoS in IEEE 802.11 Wireless Networks

Research paper thumbnail of Improving IEEE 802.11 to Support Quality of Service in Wireless Networks

Research paper thumbnail of Improving Ieee 802.11 G Mac to Support Quality of Service for Multimedia Applications in Wireless Networks

This paper paper investigates, describes and propose better techniques to provide QoS by assignin... more This paper paper investigates, describes and propose better techniques to provide QoS by assigning new metrics to the DCF access method, involving the DCF Interframe Space (DIFS), Contention Window values and the maximum data packet size to high priority nodes, which will bias towards high priority multimedia traffic to support QoS. A simulation is done using Network Simulator 2 (NS-2) and comparisons were made between different sets of network simulation scenarios. Improvements on throughput, delay and jitter can clearly be seen and further analysis is then presented.

Research paper thumbnail of Assessing Wireless Security Implementation in Government and Private Sector Companies in Malacca–A Case Study

Research paper thumbnail of DIFS Modifications to Support QoS in IEEE 802.11 g DCF Ad-hoc Networks

Research paper thumbnail of A novel approach on teaching network security for ICT courses

2009 International Conference on Engineering Education (ICEED), 2009

This paper discusses a curriculum approach that will give emphasis on practical sessions of teach... more This paper discusses a curriculum approach that will give emphasis on practical sessions of teaching network security subjects in information and communication technology courses. As we are well aware, the need to use a practice and application oriented approach in education is paramount [1]. Research on active learning and cooperative groups showed that students grasps and have more tendency towards obtaining and realizing soft skills like leadership, communication and team work as opposed to learning using the traditional theory and exam based method. While this teaching and learning paradigm is relatively new in Malaysia, it has been practiced widely in the West. This paper examines a particular approach whereby students learning wireless security are divided into small manageable groups consisting of black hat and white hat team. The former will try to find and expose vulnerabilities in a wireless network while the latter will try to prevent such attacks on their wireless networks using hardware, software, design and enforcement of security policy and etc. This paper will try to demonstrate whether this approach will result in a more fruitful outcome in terms of students concept and theory understandings and motivation to learn.

Research paper thumbnail of Performance enhancements in IEEE 802.11 DCF MANET through variation of SIFS values in distance vector routing environment

2011 7th International Conference on Information Technology in Asia, 2011

Research paper thumbnail of Retransmission-based additional TXOP allocation for audio-video transmission by IEEE 802.11e HCCA

2011 7th International Conference on Information Technology in Asia, 2011

Abstract This paper proposed a method of allocating additional TXOP duration to replenish the ban... more Abstract This paper proposed a method of allocating additional TXOP duration to replenish the bandwidth used during the retransmission of frames at link layer in audio-video transmission by IEEE 802.11 e HCCA. In the proposed scheme, the HC monitors the ...

Research paper thumbnail of New Approach in Teaching Network Security Subjects

... Mohammad Radzi Motsidi; Mohd Fairuz Iskandar Othman; Yahaya Abd Rahim; Mohd Najwan Khambari F... more ... Mohammad Radzi Motsidi; Mohd Fairuz Iskandar Othman; Yahaya Abd Rahim; Mohd Najwan Khambari Faculty of Information and Communication Technology, Universiti Teknikal Malaysia Melaka (UTeM) Karung Berkunci 1752 ... [3] Hassan, I., Ayob, MR, Sulaiman, M., Md Tahir ...