Optical encryption interface

An analog optical encryption system based on phase scrambling of two-dimensional optical images and holographic transformation for achieving large encryption keys and high encryption speed. An enciphering interface uses a spatial light modulator for converting a digital data stream into a two dimensional optical image. The optical image is further transformed into a hologram with a random phase distribution. The hologram is converted into digital form for transmission over a shared information channel. A respective deciphering interface at a receiver reverses the encrypting process by using a phase conjugate reconstruction of the phase scrambled hologram

Studying Security Issues in HPC (Super Computer) Environment

HPC has evolved from being a buzzword to becoming one of the most exciting areas in the field of Information Technology & Computer Science. Organizations are increasingly looking to HPC to improve operational efficiency, reduce expenditure over time and improve the computational power. Using Super Computers hosted on a particular location and connected with the Internet can reduce the installation of computational power and making it centralise. However, centralise system has some advantages and disadvantages over the distributed system, but we avoid discussing those issues and focusing more on the HPC systems. HPC can also be used to build web and file server and for applications of cloud computing. Due to cluster type architecture and high processing speed, we have experienced that it works far better and handles the loads in much more efficient manner then series of desktop with normal configuration connected together for application of cloud computing and network applications. In this paper we have discussed on issues re lated to security of data and information on the context of HPC. Data and information are vanurable to security and safety. It is the purpose of this paper to present some practical security issues related to High Performance Computing Environment. Based on our observation on security requirements of HPC we have discuss some existing security technologies used in HPC. When observed to various literatures, we found that the existing techniques are not enough. We have discussed, some of the key issues relating to this context. Lastly, we have made an approach to find an appropriate solution using Blowfish encryption and decryption algorithm. We hope that, with our proposed concepts, HPC applications to perform better and in safer way. At the end, we have proposed a modified blow fish algorithmic technique by attaching random number generator algorithm to make the encryption decryption technique more appropriate for our own HPC environment

Security in mobile agent systems: an approach to protect mobile agents from malicious host attacks

Mobile agents are autonomous programs that roam the Internet from machine to machine under their own control on behalf of their users to perform specific pre-defined tasks. In addition to that, a mobile agent can suspend its execution at any point; transfer itself to another machine then resume execution at the new machine without any loss of state. Such a mobile model can perform many possible types of operations, and might carry critical data that has to be protected from possible attacks. The issue of agent security and specially agent protection from host attacks has been a hot topic and no fully comprehensive solution has been found so far. In this thesis, we examine the possible security attacks that hosts and agents suffer from. These attacks can take one of four possible forms: Attacks from host to host, from agents to hosts, from agents to agents (peer to peer) and finally from hosts to agents. Our main concern in this thesis is these attacks from a malicious host on an agent. These attacks can take many forms including rerouting, spying out code, spying out data, spying out control flow, manipulation of code, manipulation of data, manipulation of control flow, incorrect execution of code, masquerading and denial of execution. In an attempt to solve the problem of malicious host attacks on agents, many partial solutions were proposed. These solutions ranged across simple legal protection, hardware solutions, partitioning, replication and voting, components, self-authentication, and migration history. Other solutions also included using audit logs, read-only state, append only logs, encrypted algorithms, digital signatures, partial result authentication codes, and code mess-up, limited life time of code and data as well as time limited black box security. In this thesis, we present a three-tier solution. This solution is a combination of code mess up, encryption and time out. Choosing code mess-up as part of the solution was due to the several strengths of this method that is based on obfuscating the features of the code so that any attacker will find it very difficult to understand the original code. A new algorithm iii was developed in this thesis to implement code mess-up that uses the concept of variable disguising by altering the values of strings and numerical values. Several encryption algorithms were studied to choose the best algorithm to use in the development of the proposed solution. The algorithms studied included DES, LUCIFER, MADRYGA, NEWDES, FEAL, REDOC, LOKI, KHUFU & KHAFRE, IDEA and finally MMB. The algorithm used was the DES algorithm due to several important factors including its key length. Not any language can be used to implement mobile agents. Candidate languages should possess the portability characteristic and should be safe and secure enough to guarantee a protection for the mobile agent. In addition to that the language should be efficient in order to minimize the implementation overhead and the overhead of providing safety and security. Languages used to implement mobile agents include Java, Limbo, Telescript, and Safe TCL. The Java language was chosen as the programming language for this thesis due to its high security, platform independence, and multithreading. This is in addition to several powerful features that characterize the Java language as will be mentioned later on. Implementing a mobile agent requires the assistance of a mobile agent system that helps in launching the agent from one host to another. There are many existing agent launching systems like Telescript, Aglets, Tacoma, Agent TCL and Concordia. Concordia was chosen to be the implementation tool used to launch our mobile agent. It is a software framework for developing, running and administering mobile agents, and it proved to be very efficient, and effective. The results of our proposed solutions showed the strength of the proposed model in terms of fully protecting the mobile agent from possible malicious host attacks. The model could have several points of enhancements. These enhancements include changing the code mess-up algorithm to a more powerful one, using a different encryption technique, and implementing an agent re-charge mechanism to recharge the agent after it is timeout

Iterative Characteristics of DES and S^2-DES

In this paper we show that we are close at the proof that the type of characteristics used by Biham and Shamir in their differential attack on DES are in fact the best characteristics we can find for DES. Furthermore we show that the criteria for the construction of DES-like S-boxes proposed by Kim are insufficient to assure resistance against differential attacks. We show several good iterative characteristics for these S-boxes to be used in differential attacks. Finally we examine the probabilities of the two characteristics used by Biham and Shamir. We found that for some keys we do not get the probabilities used in the attack. We suggest the use of 5 characteristics instead of two in the attack on DES

The design of a secure data communication system

The recent results of using a new type of chosen-plaintext attack, which is called differential cryptanalysis, makes most published conventional secret-key block cipher systems vulnerable. The need for a new conventional cipher which resists all known attacks was the main inspiration of this work. The design of a secret-key block cipher algorithm called DCU-Cipher, that resists all known cryptanalysis methods is proposed in this dissertation. The proposed method is workable for either 64-bit plaintext/64-bit ciphertext blocks, or 128-bit plaintext/128-bit ciphertext blocks. The secret key in both styles is 128-bit long. This method has only four rounds and the main transformation function in this cipher algorithm is based on four mixed operations. The proposed method is suitable for both hardware and software implementation. It is also suitable for cryptographic hash function implementations. Two techniques for file and/or data communication encryption are also proposed here. These modes are modified versions of the Cipher-Block Chaining mode, by which the threat of the known-plaintext differential cyptanalytical attack is averted. An intensive investigation of the best known Identity-based key exchange schemes is also presented. The idea behind using such protocols, is providing an authenticated secret-key by using the users identification tockens. These kind of protocols appeared recently and are not standardized as yet. None of these protocols have been compared with previous proposals. Therefore one can not realize the efficiency and the advantages of a new proposed protocol without comparing it with other existing schemes of the same type. The aim of this investigation is to clarify the advantages and the disadvantages of each of the best known schemes and compare these schemes from the complixity and the speed viewpoint

Структурна організація алгоритмів симетричного блокового шифрування

Досліджено базові підходи та особливості структурної організації сучасних алгоритмів симетричного блокового шифрування (АСБШ). Розроблено та досліджено структурну організацію узагальненого АСБШ. Запропоновано та досліджено структурну організацію складових процедур АСБШ, їх класифікацію, аналітичні вирази та графічну інтерпретацію. Наведені та проаналізовані основні підходи до виконання складових процедур АСБШ.Base approaches and peculiarities of the structural organization of the modern symmetric block encryption algorithm (SBEA) are investigated. A structural organization of generalized SBEA is developed and analyzed. The structural organization of the components of the SBEA procedures, their classification, the analytical equations and the graphical interpretation are proposed and investigated. The main approaches of the SBEA component parts execution are considered and analyzed

Design implementation and analysis of a dynamic cryptography algorithm with applications

Cryptographers need to provide the world with a new encryption standard. DES, the major encryption algorithm for the past fifteen years, is nearing the end of its useful life. Its 56-bit key size is vulnerable to a brute-force attack on powerful microprocessors and recent advances in linear cryptanalysis and differential cryptanalysis indicate that DES is vulnerable to other attacks as well. A more recent attack called XSL, proposes a new attack against AES and Serpent. The attack depends much more critically on the complexity of the nonlinear components than on the number of rounds. Ciphers with small S-boxes and simple structures are particularly vulnerable. Serpent has small S-boxes and a simple structure. AES has larger S-boxes, but a very simple algebraic description. If the attack is proven to be correct, cryptographers predict it to break AES with a 2; 80 complexity, over the coming years; Many of the other unbroken algorithms---Khufu, REDOC II, and IDEA---are protected by patents. RC2 is broken. The U.S. government has declassified the Skipjack algorithm in the Clipper and Capstone chips

Cryptoraptor : high throughput reconfigurable cryptographic processor for symmetric key encryption and cryptographic hash functions

textIn cryptographic processor design, the selection of functional primitives and connection structures between these primitives are extremely crucial to maximize throughput and flexibility. Hence, detailed analysis on the specifications and requirements of existing crypto-systems plays a crucial role in cryptographic processor design. This thesis provides the most comprehensive literature review that we are aware of on the widest range of existing cryptographic algorithms, their specifications, requirements, and hardware structures. In the light of this analysis, it also describes a high performance, low power, and highly flexible cryptographic processor, Cryptoraptor, that is designed to support both today's and tomorrow's encryption standards. To the best of our knowledge, the proposed cryptographic processor supports the widest range of cryptographic algorithms compared to other solutions in the literature and is the only crypto-specific processor targeting the future standards as well. Unlike previous work, we aim for maximum throughput for all known encryption standards, and to support future standards as well. Our 1GHz design achieves a peak throughput of 128Gbps for AES-128 which is competitive with ASIC designs and has 25X and 160X higher throughput per area than CPU and GPU solutions, respectively.Electrical and Computer Engineerin