Thesis (M.Eng.)--Memorial University of Newfoundland, 2004. / Restricted until May 2005. Bibliography: leaves 106-107.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 151-165.

Thesis (M.S.)--Florida State University, 2006. / Advisor: Mike Burmester, Florida State University,College of Arts amd Sciences, Dept. of Computer Science. Title and description from dissertation home page (viewed June 19, 2006). Document formatted into pages; contains viii, 40 pages. Includes bibliographical references.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 117-122). Also available in electronic version.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 88-92). Also available in electronic version.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 61-64). Also available in electronic version.

Thesis (M.S. in Electrical Engineering)--Vanderbilt University, Aug. 2007. / Title from title screen. Includes bibliographical references.

M.Ing. (Electrical and Electronic Engineering) / Please refer to full text to view abstract

Non-malleable codes, introduced by Dziembowski, Pietrzak, and Wichs (ICS 2010), provide a means of encoding information such that if the encoding is tampered with, the result encodes something either identical or completely unrelated. Unlike error-correcting codes (for which the result of tampering must always be identical), non-malleable codes give guarantees even when tampering functions are allowed to change every symbol of a codeword. In this thesis, we will provide constructions of non-malleable codes secure against a variety tampering classes with natural computational semantics: • Bounded-Communication: Functions corresponding to 2-party protocols where each party receives half the input (respectively) and then may communicate <𝒏/4 bits before returning their (respective) half of the tampered output. •Local Functions (Juntas):} each tampered output bit is only a function of n¹-ẟ inputs bits, where ẟ>0 is any constant (the efficiency of our code depends on ẟ). This class includes NC⁰. •Decision Trees: each tampered output bit is a function of n¹/⁴-⁰(¹) adaptively chosen bits. •Small-Depth Circuits: each tampered output bit is produced by a 𝒄log(n)/log log(n)-depth circuit of polynomial size, for some constant 𝒄. This class includes AC⁰. •Low Degree Polynomials: each tampered output field element is produced by a low-degree (relative to the field size) polynomial. •Polynomial-Size Circuit Tampering: each tampered codeword is produced by circuit of size 𝒏ᶜ where 𝒄 is any constant (the efficiency of our code depends on 𝒄). This result assumes that E is hard for exponential size nondeterministic circuits (all other results are unconditional). We stress that our constructions are efficient (encoding and decoding can be performed in uniform polynomial time) and (with the exception of the last result, which assumes strong circuit lower bounds) enjoy unconditional, statistical security guarantees. We also illuminate some potential barriers to constructing codes for more complex computational classes from simpler assumptions.

Chaotic encryption is currently a popular topic in technical journals. A number of articles have been written proposing novel methods of encrypting data using chaotic signals. Most of the encryption schemes rely on the ability of chaotic systems to be synchronized. Pecora and Carroll, the noted experts on this topic, have published a number of papers describing the theory and presenting simulations of synchronized circuits. Their papers are most often cited as the source of synchronization theory. However, no tests have been performed exploring synchronization across anything but ideal channels. This paper presents a brief background of chaotic signals. The basic theory of synchronizing chaotic signals is covered next. Finally a series of experiments are performed testing the ability of a chaotic signal to synchronize over various audio grade channels, the most often used medium for encrypted information. The experiments show that there are considerable problems getting chaotic circuits to synchronize over non-ideal channels. The failure to synchronize is discussed with respect to each channel tested. A number of additional research opportunities are presented. / Master of Science