Informatics Publishing Limited

Nour El Deen M. Khalifa ¹, Mohamed Hamed N. Taha ¹, Hesham N. Elmahdy ¹, Imane A. Saroit ¹

Affiliations
1 Information Technology Department, Cairo University, Cairo, EG

Abstract

Wireless Wireless Sensor Networks (WSNs) have become an important component in our daily lives. In near future, it will dominate the technology industry around the world. WSNs gain its importance due to the variety of vital applications it can participate in such as military, health care, agriculture, surveillance and monitoring natural phenomena applications. WSNs consist of small devices with limited energy and storage capabilities, called sensor nodes. The sensor nodes collect data from physical or environmental phenomena. They cooperatively pass the sensed data through the network to a certain location or sink node where the data can be collected and analyzed. Due to the unprotected nature of wireless communication channels and untrusted transmission medium of WSNs, it becomes vulnerable to many types of security attacks. The attackers ultimately seek to eavesdrop, steal confidential data, injecting false data or even jamming the whole network, so securing these networks becomes a must. In this paper, a proposed security schema for WSNs will be introduced. The proposed security schema will be appropriate for real time multimedia streaming. It will construct its security features within the application and transport layer as the information that the attackers seek ultimately exist within these layers. The proposed security schema consists of two security levels; the first level is encrypting the packet data using Advanced Encryption Standard (AES) while the second level is generating Message Authentication Code (MAC) using Cipher-based Message Authentication Code (CMAC). Both levels achieved the principles of WSNs security and they are (authentication, confidentiality, data integrity and availability). Performance comparisons between the proposed security schema and other security frameworks are presented. Finally, all the presented work in this research was developed and implemented using Network Simulator-2 (NS-2). According to our literature reviews, this research is one of the first researches that use NS-2 as a security simulator. As NS-2 does not support any security features before.

Keywords

Wireless Sensor Networks, AES, CMAC, Security Simulator, NS-2.

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Mohamed H. Taha ¹, Nour El Din M. Khalifa ¹, Hesham N. Elmahdy ¹, Imane A. Saroit ¹

Affiliations
1 Information Technology Department, Cairo University, Cairo, EG

Abstract

Wireless sensor networks (WSNs) have become an attracted research and industry interest. In WSN, each node is attached to a battery, which supply the node with energy required for data sensing, processing and transmission. Transmitted packets are queued at intermediate nodes. Each node schedules the queued packets by assigning priorities to each packet. Priorities are assigned to packets according to their deadlines. This method in packet prioritization does not take into consideration either the network life time or energy consumption. Besides, it may lead to dropping high energy valuable packets. In many applications, WSN lifetime is considered a very critical issue, while setting up the network. In this paper, we paper we introduce new scheduling schema, called Energy Based Scheduling schema. In this schema, packets are not only prioritized according to their deadlines but also to some energy measures related to the network. These energy measures are obtained from the network nodes and are used in packet prioritization. The proposed schema is integrated with the AODV routing protocol. The unused bits in the AODV packets are used by the proposed schema in assigning sending priorities to each packet in the network. Through this paper, we will compare the proposed scheduling schema against the Basic Priority Scheduling schema, using NS-2. Comparisons are done according the network life time and energy consumption.

Keywords

Wireless Sensor Networks, Scheduling Schema, AODV, NS-2.

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Nour El Din M. Khalifa ¹, Mohamed H. Taha ¹, Hesham N. Elmahdy ¹, Imane A. Saroit ¹

Affiliations
1 Information Technology Department, Cairo University, Cairo, EG

Abstract

Wireless sensor networks (WSNs) are usually deployed for gathering data from unattended or hostile environments. Therefore, securing data transmission across these environments is a must. Due to the fact that the sensors have a limited power, any security mechanism for sensor network must be energy efficient. In this paper, a secure energy efficient mechanism is introduced with a proposed scenario which leads to a significant improvement in network energy consumption. The mechanism constructs its security features in the application and transport layer as the information that the attackers seek ultimately resides within these layers. We modified the packet format for WSN. Data payload was encrypted by Advanced Encryption Standard (AES) and Message Authentication Code (MAC) was generated to assure data confidentiality and integrity. The energy consumption metric has been taken into considerations while designing and testing the mechanism to make it energy efficient as much as possible. The energy efficiency was achieved by giving a higher priority to the secured packet over the normal packet in the Interface Queue (IFQ). Through this paper, a detailed structure of the proposed mechanism is introduced and implemented using Network Simulator-2 (NS-2). This is the first research that implements security algorithms within NS-2. Since NS- 2 does not support any security features before, this research will be a
good start to begin using NS-2 as a security simulator.

Keywords

Wireless Sensor Networks, Security, Encryption, AES, MAC, NS-2, IFQ.

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Shady S. Khalifa ¹, Hesham N. Elmahdy ¹, Imane Aly Saroit ¹, S. H. Ahmed ¹

Affiliations
1 Cairo University, EG

Abstract

Bluetooth is a low-cost, low-power wireless technology initially designed for cable replacement. With the new mobile lifestyle based on battery powered devices, Bluetooth came short in satisfying the needs of the high-rate applications due to its’ limited data rate. Introducing BluetoothV3.0+HS specification in 2009, Bluetooth can now meet those demands by switching to an alternative controller based on IEEE802.11g radio. To this date there is no published work on the performance of IEEE802.11g as an alternative Bluetooth controller. Also, there has been no work related to the simulation of BluetoothV3.0 using the popular NS2 simulator. In this study, we present an implementation of BluetoothV3.0 in the NS2 simulator, discuss the shortcomings of IEEE802.11g as an alternative Bluetooth controller and propose a new alternative Bluetooth controller based on Time Hopping Impulse Radio Ultra Wide Band (TH IR-UWB) technology. The results showed that though IEEE802.11g provides high throughput than Bluetooth, it failed to do so in an energy efficient manner and is highly affected by interference. UWB succeeded to meet the goals of providing multiple high data-rate, low-power and immunity to interference, making UWB a better choice as a Bluetooth controller for high-rate applications running on battery powered devices.

Keywords

Bluetooth, Energy Efficiency, IEEE802.11g, NS2 Simulation, Ultra Wide Band.

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Yasser A. Dahab ¹, Hesham N. Elmahdy ², Imane A. Saroit ²

Affiliations
1 Information Technology Department, Cairo University, Cairo, EG
2 Information Technology Department, Cairo University, Cairo, IN

Abstract

The Ad hoc On-Demand Distance Vector (AODV) routing protocol is an efficient Mobile Ad hoc NETworks (MANETs) routing protocol. It uses hop count as a metric for the path selection. AODV does not support Quality of Service (QoS) and neither any load-balancing mechanism. The performance of the network can be improved by using a load balancing mechanism. Such a mechanism transfers jobs from overloaded nodes to under loaded nodes. In this paper, we propose a new protocol called “Load-Aware AODV” (LA-AODV), to provide QoS and load-balancing features. LA-AODV is based on AODV, where protocol messages extensions are used to accomplish QoS and load-balancing features. LA-AODV is a cross-layer solution that works in conjunction with a QoS-based MAC layer. It uses only local information and does not require any additional communication or co-operation between nodes.

The path selection in LA-AODV is based on the current MAC load of the nodes. The proposed protocol selects the path with the minimum MAC load based on a metric called “MAC load indicator”. We show through simulations that LA-AODV outperforms AODV in terms of received packets, delay, and routing overhead.

Keywords

Ad hoc Networks, MANET, AODV, LA-AODV, Load balance, QoS, DCF, EDCA, DAA-EDCA, Cross Layer.

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Taha M. Mohamed ¹, Hesham N. Elmahdy ¹, Hoda M. Onsi ¹

Affiliations
1 Department of Information Technology, Cairo University, #5 Dr. Ahmed Zewail Street, EG

Abstract

Digital watermarking is intended to protect digital media against unauthorized usages. The watermark is embedded in streamed videos for copyright protection purposes. In video streaming, the watermark embedding and detection time is the main concern. The distribution of the watermarking key is another important issue.

The research aims to present a real time watermarking scheme for copyright protection in H.264 compressed videos. The proposed scheme is invisible, blind, robust, and preserves the original video bit rate. The watermarking process doesn’t require any key distribution. In this paper, a new H.264 model is introduced. The context adaptive variable length codes (CAVLC) blocks are statistically modeled. Based on the resulted CAVLC model, some of the CAVLC blocks are selected for watermarking using a user defined threshold. The watermark is embedded in the CAVLC block structure. In watermark embedding, the block’s total coefficients number (TCN) is modified. The simulation results show that, the average embedding and extraction time is zero. Moreover, high bit capacity is achieved compared to other work. The PSNR values of the watermarked videos are up to 40 dB. The embedded watermark is invisible, robust, and the embedding locations are totally hidden from the attacker. The detection algorithm is blind. Furthermore, the total file size is decreased by 8% after watermarking. So, the algorithm is more appropriate for internet applications.

Keywords

Copyright Protection, Real Time Video Watermarking, H.264 Watermarking, CAVLC Modeling, VLC Watermarking, Watermark Embedding, Watermark Extraction.

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M. E. Elhamahmy ¹, Hesham N. Elmahdy ¹, Imane A. Saroit ¹

Affiliations
1 Information Technology Department, Cairo University, Cairo, EG

Abstract

The anomaly based intrusion detection system (IDS) is widely used based on different machine learning algorithms. The IDS is usually evaluated by its ability to make accurate predictions of attacks. In case of the binary classifier IDS four possible outcomes are possible. Attacks correctly predicted as attacks (TP), or incorrectly predicted as normal (FP). Normal correctly predicted as normal (TN), or incorrectly predicted as attack (FN). However, in case of multi classifier, when a class of attack is incorrectly predicted as another class of attack, it could not be any of the existing four instances. In this paper, a new approach is proposed to evaluate the anomaly based IDS. A new proposed metric F-score per Cost (FPC) is a one value calculated for each attack predictor. A new instance misclassification of attack class “MC” is proposed to represent the cases of wrong predicted attacks as another attack class. Based on the five instances a numerical evaluation can apply different measures to quantify the performance of IDS. In order to test the effectiveness of the proposed approach, three competitors of the “KDD CUP’99” competition are selected to measure their results by the proposed metrics. The results show that it was effective to add the MC instance. It achieves deep understanding of the IDS performance, and makes it more accurate to compare different intrusion detection systems and reflects the trade-off between the harmonic mean of the sensitivity, precision of the IDS and the misclassification paid against its detection accuracy.

Keywords

Intrusion Detection System, Performance Evaluation, Machine Learning, KDD Cup’ 99 Competition.

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