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New attacks on UMTS network access
, Article 2009 Wireless Telecommunications Symposium, WTS 2009, 22 April 2009 through 24 April 2009 ; 2009 ; 9781424425884 (ISBN) ; Salimi, S ; Salahi, A ; Sharif University of Technology
Abstract
In this paper we propose two new attacks on UMTS network. Both attacks exploit the UMTS-GSM interworking and are possible in the GSM access area of UMTS network. The first attack allows the attacker to eavesdrop on the entire traffic of the victim UMTS subscriber in the GERAN coverage of the UMTS network. The second attack is an impersonation attack i.e. the attacker impersonates a genuine UMTS subscriber to a UMTS network and fools the network to provide services at the expense of the victim subscriber in its GERAN coverage. © 2009 IEEE
Analysis of H-plane waveguide discontinuities using hybrid multimode contour integral and mode matching techniques
, Article 2007 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference, IMOC, Salvador, 29 January 2007 through 1 November 2007 ; December , 2007 , Pages 840-843 ; 1424406617 (ISBN); 9781424406616 (ISBN) ; Banai, A ; Sharif University of Technology
2007
Abstract
A new hybrid method based on multimode contour integral and mode matching techniques will be introduced. It is capable of analyzing any H-plane discontinuity in a rectangular waveguide. The process is based on segmentation and dividing the structure into key building blocks. We use the multimode contour integral method to analyze the blocks including irregular shape H-plane discontinuities. In opposite to traditional contour integral method, which considers only the effect of dominant mode (TE10) on wave ports, multimode contour integral considers the effect of higher order modes (TE n0) excited by discontinuities on these ports. The mode matching technique will be used to analyze the...
A lower capacity bound of secure end to end data transmission via GSM network
, Article 2012 6th International Symposium on Telecommunications, IST 2012, 6 November 2012 through 8 November 2012 ; Novembe , 2012 , Pages 1015-1020 ; 9781467320733 (ISBN) ; Mosayebi, R ; Etemadi, S. M ; Boloursaz, M ; Behnia, F ; Sharif University of Technology
2012
Abstract
Global System for Mobile communications (GSM) is a widely spread, reliable and P2P channel through all over the world. These characteristics make GSM a channel suitable for a variety of applications in different domains especially security applications such as secure voice communication. Performance and usage of GSM applications extremely depends on the transmission data rate. Hence, transmitting data over GSM is still an attractive topic for research. This paper considers the problem of digital data transmission through the GSM voice channel. A lower capacity bound for data transmission through the GSM Adaptive Multi Rate (AMR) voice codec is presented. The GSM channel is modeled in a...
Secure data over GSM based on algebraic codebooks
, Article Proceedings of IEEE East-West Design and Test Symposium, EWDTS 2013, Rostov-on-Don ; 2013 ; 9781479920969 (ISBN) ; Kazemi, R ; Nashtaali, D ; Nasiri, M ; Behnia, F ; Sharif University of Technology
2013
Abstract
This paper considers the problem of secure data communication through the Global System for Mobile communications (GSM). The algebraic codebook method for data transmission through the Adaptive Multi Rate 12.2Kbps voice channel is investigated and its maximum achievable data rate is calculated. Based on the vocoder channel properties, the method's Bit Error Rate (BER) performance is improved by repetition coding and classification methods. Simulation results show that by simultaneous application of repetition coding and clustering methods, the decoder's performance improves about 6.5% compared to the case of no clustering for 1Kbps data communication in AMR 4.75 voice codec
An improved attack on A5/1
, Article 2011 8th International ISC Conference on Information Security and Cryptology, ISCISC 2011, 14 September 2011 through 15 September 2011, Mashhad ; 2011 , Pages 41-44 ; 9781467300773 (ISBN) ; Mohajeri, J ; Sharif University of Technology
2011
Abstract
A5/1 is a stream cipher used in GSM to provide over-the-air communication privacy. Biham and Dunkelman proposed an attack on A5/1 with time complexity of 2∧(39.91) and data complexity of 2∧(21.1) known bits and memory complexity of 32 GB. In this paper, we propose an improvement on their attack. Our improvement is identification and elimination of useless states from the precomputed table. Furthermore, we propose another way for use of table in online phase of attack that causes decreasing in the time complexity to 2∧(37.89) and memory complexity decreases to half
Anonymous authentication protocol for GSM networks
, Article International Journal of Security and Networks ; Volume 3, Issue 1 , 2008 , Pages 54-62 ; 17478405 (ISSN) ; Sattarzadeh, B ; Movaghar, A ; Sharif University of Technology
Inderscience Publishers
2008
Abstract
In this paper, we propose a new anonymous channel protocol for authentication in GSM mobile communication networks. The protocol is the result of incorporating our anonymity scheme to an efficient GSM authentication protocol proposed by Chang et al. As a result, our protocol has all the features of their scheme including anonymity. Compared with the most recent protocols in this area, such as those by Peinado and Hwang et al., we show that our scheme generally is more secure and more efficient. © 2008, Inderscience Publishers
Optimized decision feedback equalizer and comparison with MLSE algorithm for GSM channel
, Article Proceedings - 2011 UKSim 13th International Conference on Modelling and Simulation, UKSim 2011, 30 March 2011 through 1 April 2011, Cambridge ; 2011 , Pages 482-487 ; 9780769543765 (ISBN) ; Rahmati, A ; Hajisami, A ; Sharif University of Technology
2011
Abstract
In this paper, we present basic equation of efficient recursive least square algorithm based on GMSK modulation by linear superposition of amplitude modulated pulses for reduction complexity in equalizer. In this here, the DFE method be improved using of signal processing technique and soft decision which is called "generalized DFE or GDFEmethodquot;. We compare the performance and complexity GDFE with MLSE method for different channels used in GSM systems. The GDFE differs from the conventional DFE in its tap values and value of tap feedback filter related with channel length, which discussed in simulation result. Our simulation results, obtained for fading multi path channels, show that...
A methodology for mobile network security risk management
, Article ITNG 2009 - 6th International Conference on Information Technology: New Generations, 27 April 2009 through 29 April 2009, Las Vegas, NV ; 2009 , Pages 1572-1573 ; Bijani, S ; Sharif University of Technology
Abstract
Based on the risk analysis done in the GSM network of Iran a methodology for cellular mobile network risk management is established. Primarily we focus on the importance of risk management in the GSM Network and then introduce very briefly the suggested method for managing risk in Iranian GSM security. GSM Security risk evaluation is a method for increasing the efficiency of security policy in the manner that security threats and vulnerabilities against the mobile network is identified and prioritized. © 2009 IEEE
Secure Data Communication through GSM Voice Channel
, M.Sc. Thesis Sharif University of Technology ; Behnia, Fereidoon (Supervisor)
Abstract
Nowadays, with the increased penetration of wireless mobile networks (e.g. GSM, 3G, etc.), voice channels are widely available ubiquitously. This availability and wide coverage encourages utilization of such channels as a valuable available infrastructure for point to point secure data communication. This can be done either by using steganography and hiding the secure message in the voice passing through the channel or by ciphering and transmitting it through the voice channel as a speech-like signal. The proposed method for data communication or steganography through voice channels should be robust against lossy compression techniques applied by the vocoder block present in such channels....
A data modem for GSM adaptive multi rate voice channel
, Article Proceedings of IEEE East-West Design and Test Symposium, EWDTS 2013 ; 2013 ; 9781479920969 (ISBN) ; Hadavi, A. H ; Kazemi, R ; Behnia, F ; Sharif University of Technology
2013
Abstract
This paper considers the problem of digital data transmission through the Global System for Mobile communications (GSM). A data modem is presented that utilizes codebooks of Speech-Like (SL) symbols to transmit data through the GSM Adaptive Multi Rate (AMR) voice codec. Using this codebook of finite alphabet, the continuous vocoder channel is modeled by a Discrete Memory less Channel (DMC). A heuristic optimization algorithm is proposed to select codebook symbols from a database of observed human speech such that the capacity of DMC is maximized. Simulation results show that the proposed data modem achieves higher data rates and lower symbol error rates compared to previously reported...
Capacity bounds and detection schemes for data over voice
, Article IEEE Transactions on Vehicular Technology ; Volume 65, Issue 11 , 2016 , Pages 8964-8977 ; 00189545 (ISSN) ; Boloursaz, M ; Etemadi, S. M ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
Cellular networks provide widespread and reliable voice communications among subscribers through mobile voice channels. These channels benefit from superior priority and higher availability compared with conventional cellular data communication services, such as General Packet Radio Service, Enhanced Data Rates for GSM Evolution, and High-Speed Downlink Packet Access. These properties are of major interest to applications that require transmitting small volumes of data urgently and reliably, such as an emergency call in vehicular applications. This encourages excessive research to make digital communication through voice channels feasible, leading to the emergence of Data over Voice (DoV)...