Optical Propagation and Communication

Contains research objectives and summary of research on four research projects.National Aeronautics and Space Administration (Grant NGR 22-009-013)U.S. Navy - Office of Naval Research (Contract N00014-76-C-0605)Joint Services Electronics Program (Contract DAAB07-76-C-1400)National Science Foundation (Grant ENG74-00131-AO2)U. S. Air Force - Electronic Systems Division (Contract F19628-76-C-0054)National Science Foundation (Grant ENG74-03996-A1

Optical Propagation and Communication

Contains research objectives and reports on two research projects.National Science Foundation (Grant ENG78-21603)U.S. Army Research Office - Durham (Contract DAAG29-80-C-0010)Joint Services Electronics Program (Contract DAAG29-78-C-0020

Processing and Transmission of Information

Contains research objectives and summary of research.U. S. Army Research Office - Durham (Contract DAHC04-69-C-0042)U. S. Army Research Office - Durham Contract DAHCO4-71 -C-0039)Joint Services Electronics Program (Contract DAAB07-71-C-0300)National Science Foundation (Grant GK-37582)National Aeronautics and Space Administration (Grant NGL 22-009-013

Processing and Transmission of Information

Contains research objectives and summary of research on three research projects and reports on two research projects.National Aeronautics and Space Administration (Grant NGL 22-009-013)National Science Foundation (Grant GK-41464)National Science Foundation (Grant GK-41098)Joint Services Electronics Program (Contract DAAB07-74-C-0630)National Science Foundation (Grant GK-37582

Quantum Noise Randomized Ciphers

We review the notion of a classical random cipher and its advantages. We sharpen the usual description of random ciphers to a particular mathematical characterization suggested by the salient feature responsible for their increased security. We describe a concrete system known as AlphaEta and show that it is equivalent to a random cipher in which the required randomization is effected by coherent-state quantum noise. We describe the currently known security features of AlphaEta and similar systems, including lower bounds on the unicity distances against ciphertext-only and known-plaintext attacks. We show how AlphaEta used in conjunction with any standard stream cipher such as AES (Advanced Encryption Standard) provides an additional, qualitatively different layer of security from physical encryption against known-plaintext attacks on the key. We refute some claims in the literature that AlphaEta is equivalent to a non-random stream cipher.Comment: Accepted for publication in Phys. Rev. A; Discussion augmented and re-organized; Section 5 contains a detailed response to 'T. Nishioka, T. Hasegawa, H. Ishizuka, K. Imafuku, H. Imai: Phys. Lett. A 327 (2004) 28-32 /quant-ph/0310168' & 'T. Nishioka, T. Hasegawa, H. Ishizuka, K. Imafuku, H. Imai: Phys. Lett. A 346 (2005) 7

Optical Propagation and Communication

Contains reports on three research projects.Joint Services Electronics Program (Contract DAAB07-75-C-1346)National Aeronautics and Space Administration (Grant NGL 22-009-013

Optical Propagation and Communication

Contains research objectives and summary of research on three research projects, and reports on three research projects.National Aeronautics and Space Administration (Grant NGL 22-009-013)National Science Foundation (Grant ENG74-00131-A01)National Science Foundation (Grant ENG74-03996-A01

Processing and Transmission of Information

Contains research objectives, summary of research and reports on one research project.National Aeronautics and Space Administration (Grant NGL 22-009-013)Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DA 28-043-AMC-02536(E)U. S. Army Research Office - Durham (Contract DAHCO4-69-C-0042