Mohamad Raad

Analysis of the tradeoff between compression ratio and security level in real-time voice communication

This paper presents an analysis of the tradeoff between security level and compression ratio in real-time voice communication. It is hypothesized that the combination of variable bitrate compression and same length encryption will induce vulnerability to traffic analysis. The variation of packet sizes can leak information about the conversation starting with language identification, identifying certain phrases, and reconstructing phonemes. The proposed solution to this problem is to rely on constant bitrate compression or to pad the sent frames to a multiple of 16, 32, or 64 bytes.

A wideband C-shaped patch antenna for LibyaSat-1

This paper presents a wideband C-shaped patch antenna for LibyaSat-1. The two parallel slots of the upper C-shaped path are incorporated to generate a second resonant frequency and hence broaden bandwidth. The folded patch technique is used to reduce the coaxial probe length and inductance at the feed section. In addition, the Quasi Newton method is used to achieve an operating frequency of 2.215 GHz (S-band). Our simulation results show that the antenna achieves a −10-dB impedance bandwidth of 1550 MHz (2.00–3.55 GHz), and has a total gain of 6.45 dB at 2.215GHz.

Quantitative study of thresholding for device-to-device communication in 5G networks

Device-to-device (D2D) communication was introduced as one of the technologies expected to tackle the increasing demand for high data rates and the growing usage of smartphones with its consequent traffic volumes. Interference is the main problem from which D2D suffers, for which several schedulers were developed. Most of the current scheduling techniques show a significant level of complexity. One way to reduce interference for D2D is to exclude some devices in a cell from D2D communication. In this paper we propose the use of a simple noise thresholding regardless of the scheduler. A device can take part in a D2D connection only if after their transmission, the value of interference in the cell remains below a specific threshold. This paper presents a comparison between the throughput of D2D devices for the case when devices are excluded based on the noise level in a cell compared to the case where no exclusion is made. In a previous work it was found that the probability distribution of device locations significantly impacted throughput. The results from two different probability distributions are presented in this paper. This study shows that when an exclusive approach is taken, the throughput per D2D device can be probabilistically guaranteed.

Wireless robo-Pi landmine detection

The tremendous recent involvement of technology in our life generates a lot of advantages and disadvantages. Nevertheless, and in order to highly augment its positive influence, at the expense of the negatives, technology most be deployed to serve humanity and society. In this article, we highlight the importance of involving robotics, communication and data analysis in the domain of land mine detection. The main idea is to design and implement a prototype of an efficient low cost automated mine detector that will replace the current employed human detectors in the mission of detecting and extracting mines in a suspected area of land. This detector will wirelessly communicate with a server to transmit the detected information such as the location of the metal object and captured images of the land where does it exist. The proposed system will help in significantly reducing the risk poses to the human detectors lives while they are in a field of mines. Besides, automation will guarantee an easier and faster scanning process that will open the door to more developed possibilities such as automatically investigating the received big sizes of data for recognizing mines from other left behind normal objects.

Client/Server and Peer-to-Peer hybrid architecture for adaptive video streaming

Adaptive video streaming over HTTP (DASH) is a recent technology adopted as the choice for delivering videos to smart phones, TVs, portable data units. Therefore, many services providers tend to adopt it as the basis for their services. In this paper, we focus on the problem of the typical behaviour of DASH, which runs over Client/Server network architecture causing limitations in its performance in regards to the growing recent streaming technologies. Our main objective is to extend DASH implementation towards hybrid architecture between C/S and P2P communication models to guarantee the availability of the video service even in case of server saturation. In a virtualization environment, we tested our approach and the preliminary results that we obtained confirm the efficiency of the proposed idea for streaming videos in term of delay and video quality.

University customized knowledge management system (KMS)

The fundamental difference between regular, ordinary information and knowledge is that the latter comprises actionable data; that is data with practical values which can be acted upon. For this reason, knowledge management has evolved throughout the years to become an integral aspect of modern corporations and organizations as it contributes to the growth and development of these enterprises. This paper proposes the implementation of a customized knowledge management system that will be deployed and integrated as part of an existing university management system that is currently in use at the Lebanese International University. This ultimate goal of such a system is to aid in the accomplishment of administrative and academic processes more effectively and efficiently.

Improving the performance of Transport Control Protocol over 802.11 wireless networks

One of the main reasons for TCPs (Transport Control Protocol) degraded performance in 802.11 wireless networks is the TCPs interpretation that the packet loss is caused by network congestion. However, in wireless networks packet loss occurs mostly due to high bit error rate, packet corruption, and link failure. TCP performance in wired/wireless networks may be substantially improved if the causes of packet loss could be identified and appropriate rectifying measures could be taken dynamically during the lifetime of a TCP session. This paper proposes an end-to-end improvement approach to the current TCP protocol by extending the used RTO (Retransmission Time Out) in such a way it allows TCP an additional waiting time for wireless errors to get fixed. This approach is validated through numerical analysis and simulations, and then compared to the current implemented TCP protocol. The simulation results have demonstrated higher TCP performance in terms of traffic sent, and retransmission attempts. This is highly recommended for a wide range of applications in mixed wired and wireless scenarios.