An Improved Authentication Scheme with Conditional Privacy Preserving in VANETs
Seyed Mortaza
Pour Naghi
PhD student, Qom University, Qom, Iran
author
Mostafa
Barmashoori
Master's degree, Faculty of Computer Science, University of Tehran, Tehran, Iran
author
Mahmoud
Ghardeshi
Assistant Professor, Imam Hossein University, Tehran, Iran
author
text
article
2015
per
Vehicular Ad-hoc Networks (VANETs) can improve the communication between vehicles andtraffic management to control appropriate. Authentication of messages which is issued by each vehicleis the most important problem in VANETs, because the wrong messages can cause crashes and changethe traffic patterns of network. Many authentication schemes have been proposed in VANETs, each ofwhich has advantages and disadvantages. In this paper first we introduce, a brief overview of theseschemes. Then we analyse an authentication scheme for VANETs which introduced by Lee and Laiand introduce three scenarios that show their scheme is vulnerable to forgery attack. These attacksmotivated us to design a novel and secure TPD based authentication scheme satisfying all securityrequirements in VANETs. Moreover, we introduce a simulation and comparison expressing theefficiency and performance of the proposed scheme.
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
1
12
https://ecdj.ihu.ac.ir/article_200082_5b6b832817affd4b21bdf6d7b31b4967.pdf
Projection of Muli Stage Cyber Attack Based on Belief Model and Fuzzy Inference
Ali Jabbar
Rashidi
Associate Professor, Information Integration Science and Technology Research Center, Malik Ashtar University of Technology, Tehran, Iran
author
Kourosh
Dadashtabar Ahmadi
PhD student, Information Integration Science and Technology Research Center, Malik Ashtar University of Technology, Tehran, Iran
author
Farid
Samsami Khodadad
Assistant Professor, New Technologies Engineering Faculty, Amol University of New Technologies, Amol, Iran
author
text
article
2015
per
Determination of plausible future of ungoing cyber attacks enables the security analyst to make thebest defense decisions based on achieved plausibility level. To achive the plausibility level of asituation, situational estimation and high level information fusion are used. In high level informationfusion, for situation awareness of future and impact assessment of cyber attacks four componnets ofprojecting, behaviour, capability, opportunity and intent are used.Almost all of the models used for projecting multi stage cyber attacks assuming the fourcomponents independent from each other to simplify the implementation. Thus, they ignored theimpact of the components on each other and their combination ability in projecting multi stage cyberattacks.In this paper, we have presented a scheme based on belif model and fuzzy inference. Finally,the scheme has been evaluated using valid dataset, high stealth attacks and high impact and lowimpact attacks. The simulation results for the defined scenarios show accuracy increasy in projectingmulti-stage cyber attacks.
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
13
28
https://ecdj.ihu.ac.ir/article_200083_eb0ca043d271e444273d975335fa3fea.pdf
Quality enhancement of received video using secondary channel encoding in Joint Source and Channel Coding (JSCC)
Pouria
Etezadifar
PhD student, Birjand University, Birjand, Iran
author
Hassan
Farasi
Associate Professor, Birjand University, Birjand, Iran
author
Ali
Naseri
Associate Professor, Imam Hossein University, Tehran, Iran
author
text
article
2015
per
Progress of technology in recent decade causes that video transmission via communicationchannels has met high demands. Therefore, several methods have been proposed to improve thequality of video under channel errors. The aim of this paper is to increase PSNR for synthesizedvideoby increasing channel encoder rate but in constant transmission rate.This is achieved by usingintelligent neural network and Huffman used in the MPEG standard to compress transmitted datasignificantly. Then,depending to the amount of compression by the proposed method, the compresseddata is coded again using secondary channel encoder. The proposed method is able to increasechannel coding rate without increasing the amount of information for each frame. This methodprovides more robustness for video frames against channel errors. The proposed method is tested fordifferent source coding rates and several SNRs for channel and the obtained results are comparedwith state-of-the-art methods.
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
29
48
https://ecdj.ihu.ac.ir/article_200084_26f792d2e265cc7280db0d43440d1f85.pdf
Enhancing Communication Security in Cellular Communications Networks by using Interference Alignment Technique
Ali
Golestani
Master's student, Khajeh Nasiruddin Toosi University of Technology, Tehran, Iran
author
Kamal
Mahamedpour
Professor, Khajeh Nasiruddin Toosi University of Technology, Tehran, Iran
author
Ali
Habibi Bastami
Assistant Professor, Khajeh Nasiruddin Toosi University of Technology, Tehran, Iran
author
text
article
2015
per
One of the common challenges in wireless communications networks is wiretapping broadcastsignals from radio stations by eavesdroppers. In this paper is shown that interference alignment (IA)technique can be completely eliminated intra and inter-cell interferences, in a cellularcommunications network with the same frequency allocation to all of the users. Also, this technique isable to provide maximum degrees of freedom (DoF) and securing the communication againsteavesdropping. IA approximately can close the rate of network secrecy to rate region of the interferingbroadcast channel (IFBC) in high SNR regime. In order to prove the mathematical and intuitivecapability of the interference alignment technique in increasing communication security, a kind of IAalgorithm closed-form is used in the downlink of an unsecured cellular network. Simulation results aredemonstrated for a certain range from the number of eavesdropper’s receive antennas, that secrecyrate well possible come close to the network sum-capacity in high SNRs.
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
49
60
https://ecdj.ihu.ac.ir/article_200085_4422a4dc3cfd1943097d8e39c6f63442.pdf
Sequential Decoding Algorithms of Convolutional Codes: Implementation, Improvement and Comparison
Mohammad
Hadi
Doctoral student of telecommunications, Sharif University of Technology, Tehran, Iran
author
Mohammad Reza
Pakravan
Associate Professor, Sharif University of Technology, Tehran, Iran
author
text
article
2015
per
Error correction capability of convolutional codes is improved by increasing code constraintlength. However, increasing the constraint length results in high complexity of optimum Viterbidecoding algorithm because the number of computations in Viterbi algorithm is exponentiallyproportional to the constraint length. Consequently, decoding of high constraint length convolutionalcodes using Viterbi algorithm may practically be impossible. Sub-optimum decoding algorithms suchas Fano and Stack algorithms have been proposed to feasible fast sequential decoding of highconstraint length convolutional codes. In this paper, we introduce different methods of implementingFano and Stack algorithms and propose some techniques to improve their speed and requiredmemory. We compare the introduced implementations of the algorithms in terms of error correctioncapability, decoding time and required memory. Furthermore, we use simulation results to show thatif the communication error is low, Fano and Stack algorithms can provide the same error correctioncapability as the optimum Viterbi algorithm in very short decoding time
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
61
73
https://ecdj.ihu.ac.ir/article_200086_06f85232861efec254659ef1f3729d70.pdf
A New Method for Detection of Discrete Data Transmitted over Non-Linear Dynamic Wireless Channels
Mohammad Hassan
Majidi
Assistant Professor, Faculty of Electrical and Computer Engineering, Birjand University, Birjand, Iran
author
text
article
2015
per
In this paper, channel estimation and data detection under non linear time-varying channel areinvestigated. The model of non linear time varying channel that we focused on is known as switchingstate space model (SSSM). This model combines the hidden Markov model (HMM) and the linear statespace model (LSSM). In this paper based on the EM approach, we propose a new iterative method forjoint data detection and channel estimation. Monte Carlo simulations show that the bit error rate(BER) of the proposed scheme is close to BER of the Viterbi algorithm (VA) with perfect channel stateinformation (CSI).
Electronic and Cyber Defense
Imam Hussein University
2322-4347
3
v.
2
no.
2015
75
85
https://ecdj.ihu.ac.ir/article_200087_cc5ed4971a42e8ea153dfc6cc0d93272.pdf