The constant matrix multiplication is one of the key operations in many applications including digital signal processing, communication, and coding. In general, constant matrix multiplication can be expressed as bit-level Boolean functions. Then, common subexpression elimination (CSE) can be used to reduce the area cost of realizing these bit-level functions by finding the shared common factors among these bit-level equations. The proposed circuit generator performs logic reduction on the input Boolean functions and produces the simplified Verilog HDL codes as output. Then the simplified code is fed into Synopsys Design Compiler for further logic minimization and technology mapping to generate gate-level netlists. In this thesis, we present ten different CSE algorithms for logic reduction of the bit-level Boolean functions. The comparisons include both the architecture-level technology-independent results and the Synopsys synthesized technology-dependent results. According to the experiments, we observe that our CSE can effectively reduce the area cost. We also apply the CSE to the design of the Advanced Encryption Standard (AES) in cryptography.

<p>Today increasing numbers of individuals are working away from the ordinary workplace while still requiring access to the server located at the workplace. New technology is meeting this demand allowing for safe and secure transmission of the data over the Internet. The aim of this project is to analyse two protocols that are used within the Virtual Private Network (VPN) structure today, with the focus on installation, transmission speed on both Local Area Networks (LAN) and via telephone line and security aspects of the protocols.</p><p>The results show that it is quite complicated to setup a VPN network and to get operational. The results also show that there are security compromises within the VPN structure that indicate that if proper precaution is not taken it may give a false sense of security, where the user believes that it is a secure communication when in reality it is not.</p>

Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Dinolt, George. Second Reader: Eagle, Chris. "December 2009." Description based on title screen as viewed on January 27, 2010. Author(s) subject terms: Distributed password cracking, Berkeley Open Infrastructure for Network Computing (BOINC), and John the Ripper. Includes bibliographical references (p. 63-64). Also available in print.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Yvo Desmedt, Florida State University, College of Arts and Sciences, Dept. of Computer Science. Title and description from dissertation home page (June 18, 2004). Includes bibliographical references.

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references. Also available in electronic version. Access restricted to campus users.

This thesis presents an analysis of the implementation feasibility of RAM authentication and encryption. Past research as used simulations to establish that it is possible to authenticate and encrypt the contents of RAM with reasonable performance penalties by using clever implementations of tree data structures over the contents of RAM. However, previous work has largely bypassed implementation issues such as power consumption and silicon area required to implement the proposed schemes, leaving implementation details unspecified. This thesis studies the implementation cost of AES-GCM hardware and software solutions for memory authentication and encryption and shows that software solutions are infeasible because they are too costly in terms of performance and power, whereas hardware solutions are more feasible. / text

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Ο βασικός στόχος της παρούσας διπλωματικής εργασίας είναι η δημιουργία μίας βιβλιοθήκης συναρτήσεων κρυπτογράφησης γραπτού κειμένου, η οποία να μπορεί στην συνέχεια να επεξεργαστεί και να αναπτυχθεί περεταίρω με την προσθήκη νέων συναρτήσεων ή ακόμη και με την βελτίωση των ήδη υπαρχόντων. Στα πλαίσια της υλοποιήθηκαν τέσσερεις συναρτήσεις κρυπτογράφησης-αποκρυπτογράφησης οι οποίες παρουσιάζονται αναλυτικά στο κείμενο της εργασίας. Οι συναρτήσεις αυτές συγκρίνονται ως προς την ταχύτητά τους με τον αλγόριθμο κρυπτογράφησης DES (Data Encryption Standard) από όπου προκύπτει ότι μία εξ αυτών επιτυγχάνει μικρότερους χρόνους κρυπτογράφησης-αποκρυπτογράφησης, ενώ οι χρόνοι των υπολοίπων τριών είναι ελαφρώς υψηλότεροι. Τέλος πραγματοποιείται μία εκτίμηση ως προς την ασφάλεια που παρέχεται από την χρήση των συγκεκριμένων συναρτήσεων. / The main goal of this diploma dissertation is to create a library of cryptographic functions applied in text, which can then be able to be processed and further more expand by adding new functions or even by improving the existing ones. Within the framework of this dissertation four encryption-decryption functions were created, which are widely presented in this text. The speed of these functions is compared to the algorithm DES (Data Encryption Standard) from which results that one of them achieves faster times of encryption-decryption while the other are taking slightly longer to complete. Finally, an estimation is carried out as far as the safety provided by the use of these specific functions.

No description available.

Over the last decade, the demand for privacy and data confidentiality in communication and storage processes have increased exponentially. Cryptography can be the solution for this demand. However, the critical issue occurs when there is a need for computing publicly on sensitive information or delegating computation to untrusted machines. This must be done in such a way that preserves the information privacy and accessibility. For this reason, we need an encryption algorithm that allows computation on information without revealing details about them. In 1978 Rivest, Adleman and Dertouzos raised a crucial question: can we use a special privacy homomorphism to encrypt the data and do an unlimited computations on it while it remains encrypted without the necessity of decrypting it? Researchers made extensive efforts to achieve such encryption algorithm. In this paper, we introduce the implementation of the CRT-based somewhat homomorphic encryption over the integers scheme. The main goal is to provide a proof of concept of this new and promising encryption algorithm. / Graduate