Analisa Implementasi Algoritma Stream Cipher Sosemanuk dan Dicing dalam Proses Enkripsi Data

Keamanan merupakan hal yang diutamakan dalam sistem informasi, khususnya dalam pertukaran data yang bersifat penting atau rahasia. Informasi yang akan diberikan kepada pihak yang berhak terhadap informasi tersebut harus benar-benar dijaga tingkat keamanannya, jangan sampai jatuh ke tangan pihak lain yang tidak punya hak akan informasi tersebut.Salah satu cara untuk menjaga keamanan informasi yang dipertukarkan dalan suatu sistem dapat dilakukan dengan menggunakan teknik kriptografi. Kriptografi merupakan seni dan ilmu untuk menyembunyikan informasi dari pihak ketiga. Dalam kriptografi seseorang yang memiliki kunci privat dapat mengubah data asli (plaintext) menjadi data yang bersifat unik dan tidak dapat dibaca (ciphertext) dan dapat mengubah kembali ciphertext yang ada ke dalam bentuk plaintext dengan menggunakan kunci privat yang dimilikinya.Dalam penelitian ini telah berhasil dibuat suatu sistem kriptografi menggunakan algoritma Sosemanuk dan Dicing dan diimplementasikan menggunakan Borland C++ Builder 6.0. Penelitian ini bertujuan untuk menganalisa perbandingan performansi antara algoritma Sosemanuk dan Dicing dalam hal kecepatan proses enkripsi dan dekripsi, memori yang dibutuhkan selama proses, dan nilai avalanche effect.Berdasarkan hasil penelitian dapat disimpulkan bahwa nilai Avalanche Effect (AV) algoritma Sosemanuk lebih besar daripada algoritma Dicing, sehingga algoritma Sosemanuk lebih handal daripada algoritma Dicing. Proses pada algoritma Sosemanuk lebih kompleks daripada algoritma Dicing, sehingga waktu yang diperlukan oleh algoritma Sosemanuk 4,77 % lebih lama dan memori yang diperlukan lebih besar daripada algoritma Dicing. Tipe file tidak berpengaruh terhadap lama waktu enkripsi ataupun dekripsi, karena file dibaca per byte

Improved Linear Cryptanalysis of SOSEMANUK

Abstract. The SOSEMANUK stream cipher is one of the finalists of the eSTREAM project. In this paper, we improve the linear cryptanalysis of SOSEMANUK presented in Asiacrypt 2008. We apply the generalized linear masking technique to SOSEMANUK and derive many linear approximations holding with the correlations of up to 2 −25.5. We show that the data complexity of the linear attack on SOSEMANUK can be reduced by a factor of 2 10 if multiple linear approximations are used. Since SOSEMANUK claims 128-bit security, our attack would not be a real threat on the security of SOSEMANUK. Keywords: Stream Ciphers, Linear Cryptanalysis, SOSEMANUK, SOBER-128.

New Treatment of the BSW Sampling and Its Applications to Stream Ciphers

By combining the time-memory-data tradeoff (TMDTO) attack independently proposed by Babbage and Golic (BG) with the BSW sampling technique, this paper explores to mount a new TMDTO attack on stream ciphers. The new attack gives a wider variety of trade-offs, compared with original BG-TMDTO attack. It is efficient when multiple data is allowed for the attacker from the same key with different IVs, even though the internal state size is twice the key size. We apply the new attack to MICKEY and Grain stream ciphers, and improves the existing TMDTO attacks on them. Our attacks on Grain v1 and Grain-128 stream ciphers are rather attractive in the respect that the online time, offline time and memory complexities are all better than an exhaustive key search, and the amount of keystream needed are completely valid. Finally, we generalize the new attack to a Guess and Determine-TMDTO attack on stream ciphers, and mount a Guess and Determine-TMDTO attack on SOSEMANUK stream cipher with the online time and offline time complexities both equal to 2128, which achieves the best time com-plexity level compared with all existing attacks on SOSEMANUK so far

A fast and light stream cipher for smartphones

We present a stream cipher based on a chaotic dynamical system. Using a chaotic trajectory sampled under certain rules in order to avoid any attempt to reconstruct the original one, we create a binary pseudo-random keystream that can only be exactly reproduced by someone that has fully knowledge of the communication system parameters formed by a transmitter and a receiver and sharing the same initial conditions. The plaintext is XORed with the keystream creating the ciphertext, the encrypted message. This keystream passes the NISTs randomness test and has been implemented in a videoconference App for smartphones, in order to show the fast and light nature of the proposed encryption system

Survey on Lightweight Primitives and Protocols for RFID in Wireless Sensor Networks

The use of radio frequency identification (RFID) technologies is becoming widespread in all kind of wireless network-based applications. As expected, applications based on sensor networks, ad-hoc or mobile ad hoc networks (MANETs) can be highly benefited from the adoption of RFID solutions. There is a strong need to employ lightweight cryptographic primitives for many security applications because of the tight cost and constrained resource requirement of sensor based networks. This paper mainly focuses on the security analysis of lightweight protocols and algorithms proposed for the security of RFID systems. A large number of research solutions have been proposed to implement lightweight cryptographic primitives and protocols in sensor and RFID integration based resource constraint networks. In this work, an overview of the currently discussed lightweight primitives and their attributes has been done. These primitives and protocols have been compared based on gate equivalents (GEs), power, technology, strengths, weaknesses and attacks. Further, an integration of primitives and protocols is compared with the possibilities of their applications in practical scenarios

ANALISA IMPLEMENTASI ALGORITMA STREAM CIPHER SOSEMANUK DAN DICING DALAM PROSES ENKRIPSI DATA

Keamanan merupakan hal yang diutamakan dalam sistem informasi, khususnya dalam pertukaran data yang bersifat penting atau rahasia. Informasi yang akan diberikan kepada pihak yang berhak terhadap informasi tersebut harus benar-benar dijaga tingkat keamanannya, jangan sampai jatuh ke tangan pihak lain yang tidak punya hak akan informasi tersebut.Salah satu cara untuk menjaga keamanan informasi yang dipertukarkan dalan suatu sistem dapat dilakukan dengan menggunakan teknik kriptografi. Kriptografi merupakan seni dan ilmu untuk menyembunyikan informasi dari pihak ketiga. Dalam kriptografi seseorang yang memiliki kunci privat dapat mengubah data asli (plaintext) menjadi data yang bersifat unik dan tidak dapat dibaca (ciphertext) dan dapat mengubah kembali ciphertext yang ada ke dalam bentuk plaintext dengan menggunakan kunci privat yang dimilikinya.Dalam penelitian ini telah berhasil dibuat suatu sistem kriptografi menggunakan algoritma Sosemanuk dan Dicing dan diimplementasikan menggunakan Borland C++ Builder 6.0. Penelitian ini bertujuan untuk menganalisa perbandingan performansi antara algoritma Sosemanuk dan Dicing dalam hal kecepatan proses enkripsi dan dekripsi, memori yang dibutuhkan selama proses, dan nilai avalanche effect.Berdasarkan hasil penelitian dapat disimpulkan bahwa nilai Avalanche Effect (AV) algoritma Sosemanuk lebih besar daripada algoritma Dicing, sehingga algoritma Sosemanuk lebih handal daripada algoritma Dicing. Proses pada algoritma Sosemanuk lebih kompleks daripada algoritma Dicing, sehingga waktu yang diperlukan oleh algoritma Sosemanuk 4,77 % lebih lama dan memori yang diperlukan lebih besar daripada algoritma Dicing. Tipe file tidak berpengaruh terhadap lama waktu enkripsi ataupun dekripsi, karena file dibaca per byte

MV3: A new word based stream cipher using rapid mixing and revolving buffers

MV3 is a new word based stream cipher for encrypting long streams of data. A direct adaptation of a byte based cipher such as RC4 into a 32- or 64-bit word version will obviously need vast amounts of memory. This scaling issue necessitates a look for new components and principles, as well as mathematical analysis to justify their use. Our approach, like RC4's, is based on rapidly mixing random walks on directed graphs (that is, walks which reach a random state quickly, from any starting point). We begin with some well understood walks, and then introduce nonlinearity in their steps in order to improve security and show long term statistical correlations are negligible. To minimize the short term correlations, as well as to deter attacks using equations involving successive outputs, we provide a method for sequencing the outputs derived from the walk using three revolving buffers. The cipher is fast -- it runs at a speed of less than 5 cycles per byte on a Pentium IV processor. A word based cipher needs to output more bits per step, which exposes more correlations for attacks. Moreover we seek simplicity of construction and transparent analysis. To meet these requirements, we use a larger state and claim security corresponding to only a fraction of it. Our design is for an adequately secure word-based cipher; our very preliminary estimate puts the security close to exhaustive search for keys of size < 256 bits.Comment: 27 pages, shortened version will appear in "Topics in Cryptology - CT-RSA 2007