Karim H. Moussa

Dr. Karim H. Moussa

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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 February 2020 in Entropy
Verified
Journal Article
Open access
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DEDalia H. ElKamchouchi
Dalia H. ElKamchouchi
HGHeba Gaber
Heba Gaber
KMKarim H. Moussa
Karim H. Moussa
Modern multimedia communications technology requirements have raised security standards, which allows for enormous development in security standards. This article presents an innovative symmetric cryptosystem that depends on the hybrid chaotic Lorenz diffusion stage and DNA confusion stage. It involves two identical encryption and decryption algorithms, which simplifies the implementation of transmitting and receiving schemes of images securely as a bijective system. Both schemes utilize two distinctive non-consecutive chaotic diffusion stages and one DNA scrambling stage in between. The generation of the coded secret bit stream employs a hybrid chaotic system, which is employed to encrypt or decrypt the transmitted image and is utilized in the diffusion process to dissipate the redundancy in the original transmitted image statistics. The transmitted image is divided into eight scrambled matrices according to the position of the pixel in every splitting matrix. Each binary matrix is converted using a different conversion rule in the Watson–Crick rules. The DNA confusion stage is applied to increase the complexity of the correlation between the transmitted image and the utilized key. These stages allow the proposed image encryption scheme to be more robust against chosen/known plaintext attacks, differential attacks, cipher image attacks, and information entropy. The system was revealed to be more sensitive against minimal change in the generated secret key. The analysis proves that the system has superior statistical properties, bulkier key space, better plain text sensitivity, and improved key sensitivity compared with former schemes.

29 January 2020 in Entropy
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Journal Article
Open access
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HGHeba Gaber
Heba Gaber
DEDalia H. ElKamchouchi
Dalia H. ElKamchouchi
KMKarim H. Moussa
Karim H. Moussa
Multimedia encryption innovation is one of the primary ways of securely and privately guaranteeing the security of media transmission. There are many advantages when utilizing the attributes of chaos, for example, arbitrariness, consistency, ergodicity, and initial condition affectability, for any covert multimedia transmission. Additionally, many more benefits can be introduced with the exceptional space compliance, unique information, and processing capability of real mitochondrial deoxyribonucleic acid (mtDNA). In this article, color image encryption employs a confusion process based on a hybrid chaotic map, first to split each channel of color images into n-clusters; then to create global shuffling over the whole image; and finally, to apply intrapixel shuffling in each cluster, which results in very disordered pixels in the encrypted image. Then, it utilizes the rationale of human mitochondrial genome mtDNA to diffuse the previously confused pixel values. Hypothetical examination and trial results demonstrate that the anticipated scheme exhibits outstanding encryption, as well as successfully opposes chosen/known plain text, statistical, and differential attacks.

25 July 2021 in Micromachines
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Journal Article
Open access
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KMKarim H. Moussa
Karim H. Moussa
ASAhmed Sayed
Ahmed Sayed
Mohamed MabroukMohamed Mabrouk
Mohamed Mabrouk
HGHeba Gaber
Heba Gaber
In contemporary wireless communication systems, the multiple-input and multiple-output systems are extensively utilized due to their enhanced spectral efficiency and diversity. Densely packed antenna arrays play an important role in such systems to enhance their spatial diversity, array gain, and beam scanning capabilities. In this article, a slotted meta-material decoupling slab (S-MTM-DS) with dual reflexes slotted E-shapes and an inductive stub is proposed. Its function was validated when located between two microstrip patch antenna elements to reduce the inter-element spacing, the mutual coupling, the return losses, and manufacturing costs due to size reduction. A prototype is simply fabricated in a volume of 67.41 × 33.49 × 1.6 mm3 and frequency-span measured from 8.4:11 GHz. At 9.4 GHz frequency, the spaces between the transmitting elements are decreased to 0.57 of the free space wavelength. When the proposed isolation S-MTM-DS is applied, the average isolation among them is measured to be −36 dB, the operational bandwidth is enhanced to be 1.512 GHz, the fractional bandwidth improved to be 16.04%, and the return losses are decreased to be −26.5 dB at 9.4 GHz center frequency. Consequently, the proposed design has the potential to be implemented simply in wireless contemporary communication schemes.

1 August 2022 in IEEE Access
Verified
Journal Article
Open access
KMKarim H. Moussa
Karim H. Moussa
AEAhmed H. El-Sakka
Ahmed H. El-Sakka
SSShawky Shaaban
Shawky Shaaban
HKHassan Nadir Ahmed Hosni Kheirallah
Hassan Nadir Ahmed Hosni Kheirallah
4G mobile communication is a global technology. Therefore, it is essential to enforce confidentiality between mobile users and their networks. This paper presents a Group Security Authentication and Key Agreement Protocol Built by Elliptic Curve Diffie Hellman Key Exchange (GSAKA-ECDHKE) to overcome and address the LTE networks Evolved Packet System Authentication and Key Agreement Protocol (EPS-AKA) protocol flaws and vulnerabilities. GSAKA-ECDHKE is presented for 4G mobile military group communications to provide security, confidentiality, and privacy while the users and networks authenticate. By embedding the Group Commander (GC) role in the EPS-AKA protocol to control the member authentication in the group. GSAKA-ECDHKE protocol is based on Elliptic Curve Diffie Hellman Key Exchange (ECDHKE) and hash function to generate and share secret Elliptic Curve (EC) key to encrypt and protect the routing authentication parameters. The Automated Validation of Internet Security Protocols and Applications (AVISPA) tool is used for security analysis and formal verification. AVISPA demonstrated that GSAKA-ECDHKE had overcome various known security attacks such as Man In The Middle (MITM), replay attacks, and Denial of Services (DoS) attacks, satisfying the evaluated security requirements. Additionally, the suggested protocol provides the lowest communication overheads compared to the existing group-based AKA protocols.

27 September 2022 in Wireless Networks
Verified
Journal Article
Open access
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KMKarim H. Moussa
Karim H. Moussa
SSShawki Shaaban
Shawki Shaaban
AEAhmed H. El-Sakka
Ahmed H. El-Sakka
The polar code is a unique coding approach that can achieve Shannon's capacity in modern communication systems' discrete memory-less channels with superior reliability, but it is not secure enough under modern attacks for such systems. This study aims to offer a comprehensive secured polar coding scheme that uses a combination of polar coding and the Mersenne-Twister pseudo-random number generator (MT-PRNG) to achieve a super secured encoding. The pre-shared crypto-system cyphering key initiates the starting state of the MT-PRNG as a seed. The randomly generated sequences govern the values of the frozen bits in polarized bit channels and their associated indices. A half-bit-error-rate probability system performance is calculated when the encoding ciphering keys at the receiver differ by a single bit from those utilized at the transmitter. Using calculated numerical analysis, the system is shown to be secure against brute force attacks, Rao-Nam attacks, and polar code reconstruction attacks.

13 October 2016 in Telecommunication Systems
Verified
Journal Article
Closed access
PDF file
SESaid El-Khamy
Said El-Khamy
KMKarim H. Moussa
Karim H. Moussa
AEAmr El-Sherif
Amr El-Sherif