Cryptology and Data Communications

Research reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program supported in part by the Advanced Research Projects Agency of the Department of Defense and monitored by the office of Naval Research under contract N00014-75-C-0643.This paper is divided into two parts. The first part deals with cryptosystems and cryptanalysis. It surveys the basic information about cryptosystems and then addresses two specific questions. Are cryptosystems such as LUCIFER which are based on the ideas of Feistel and Shannon secure for all practical purposes? Is the proposed NBS standard cryptosystem secure for all practical purposes? This paper argues that the answer to the first question is "they might well be" and that the answer to the second is "no." The second part of this paper considers how a cryptosystem can be used to provide security of data transmission in a computer environment. It discusses the two basic aspects of security: secrecy and authentication. It then describes and discusses a specific proposal by Kent of a set of protocols designed to provide security through encryption. Finally, an alternate proposal is given in order to explore some of the other design choices which could have been made.MIT Artificial Intelligence Laboratory Department of Defense Advanced Research Projects Agenc

Musipher: Hiding information in music composition

In this paper, we present a new way of hiding information. We store the information directly in the process of composing music, based on musical theory. We created an algorithm to produce music based on binary string, where each bit is transformed into a music composition decision. We follow simple rules to make music, which sounds good. We conducted survey to find whether our solution works, and found promising results of our approach

Analysis of term roles along taxonomy nodes by adopting discriminant and characteristic capabilities

Taxonomies are becoming essential to a growing number of application, particularly for specific domains. Taxonomies, originally built by hand, have been recently focused on their automatic generation. In particular, a main issue on automatic taxonomy building regards the choice of the most suitable features. In this paper, we propose an analy- sis on how each feature changes its role along taxonomy nodes in a text categorization scenario, in which the features are the terms in textual documents. We deem that, in a hierarchical structure, each node should intuitively be represented with proper meaningful and discriminant terms (i.e., performing a feature selection task for each node), instead of con- sidering a fixed feature space. To assess the discriminant power of a term, we adopt two novel metrics able to measure it. Our conjecture is that a term could significantly change its discriminant power (hence, its role) along the taxonomy levels. We perform experiments aimed at proving that a significant number of terms play different roles in each taxonomy node, giving emphasis to the usefulness of a distinct feature selection for each node. We assert that this analysis should support automatic taxonomy building approaches

Critical analyses of some public-key cryptosystems for high-speed satellite transmission applications

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.Vita.Bibliography: leaves 83-86.by Moses Hsingwen Ma.M.S

Steganography: Forensic, Security, and Legal Issues

Steganography has long been regarded as a tool used for illicit and destructive purposes such as crime and warfare. Currently, digital tools are widely available to ordinary computer users also. Steganography software allows both illicit and legitimate users to hide messages so that they will not be detected in transit. This article provides a brief history of steganography, discusses the current status in the computer age, and relates this to forensic, security, and legal issues. The paper concludes with recommendations for digital forensics investigators, IT staff, individual users, and other stakeholders