Research Publications 
(ordered by area and topic)
Neal R. Wagner

Straight list of All publications, Google Scholar Entries.

Mathematics.

    Related to retractions on 2-manifolds. [This is Ph.D. dissertation work continued for five years.]
    1. Wagner, N.R. Global properties of the space of retractions of the two-sphere and the annulus, Doctoral Dissertation, University of Illinois at Urbana-Champaign, 1970, 82 pages.
    2. Wagner, N.R. ``The space of retractions of the 2-sphere and the annulus," Transactions of the American Mathematical Society, Vol. 158 (1971), No. 2, pp. 319-329. PDF copy.
    3. Wagner, N.R. ``The space of retractions of a 2-manifold," Proceedings of the American Mathematical Society, Vol. 34 (1972), No. 2, pp. 609-614. PDF copy.
    4. Wagner, N.R. ``A continuity property and surface topology, Bulletin of the American Mathematical Society, Vol. 79 (1973), No. 6, pp. 1308-1311. PDF copy.
    5. Wagner, N.R. ``A continuity property with applications to the topology of 2-manifolds," Transactions of the American Mathematical Society, Vol. 200 (1975), pp. 369-393. PDF copy.

    Recreational mathematics (pentacube constructions). [Work done during graduate school, to keep from going crazy. See pentacubes and the 7-by-7-by-5 container: Dowler's box, from Knuth.]
    1. Wagner, N.R. ``Constructions with pentacubes," Journal of Recreational Mathematics, Vol. 5 (1972), No. 4, pp. 266-268. PDF copy.
    2. Wagner, N.R. ``Constructions with pentacubes II," Journal of Recreational Mathematics, Vol. 6 (1973), No. 3, pp. 211-214. PDF copy.

    Other mathematics.
    1. Wagner, N.R. ``The sofa problem," American Mathematical Monthly, Vol. 83 (1976), No. 3, pp. 188-189. PDF copy. [This could almost be called an early genetic algorithm. See Moving sofa problem, which references this article. See also Two-way Sofa.]
    2. Wagner, N.R. ``The faceless clock," Mathematics Teacher, Vol. 70 (1977), No. 9, p. 765. PDF copy. [Short note.]
    3. Wagner, N.R. ``A computer search for integer values of 2C and 3C," unpublished manuscript, results announced in American Mathematical Monthly, December, 1977. PDF copy. [Evidently the conjecture is true in case Schanuel's conjecture is true, but that is still open. I never thanked NASA for a day or so of unauthorized CPU time on a CDC 6400 in 1975.]
      Note: 2log372696450718 = 7126098.99999 99999 99699 557 ...

Computer Science.

    Cryptosystems based on combinatorial group theory. [In 1984 I looked at problems harder than NP-complete on which to base a public-key cryptosystem. I hit on using the undecidable Word Problem for finitely-presented groups. After my 1984 articles, a large amount of work in this area has appeared, much of it referencing my paper directly or indirectly. I seem to have the first publication presenting this approach. See the 2006 seminar in this area (local copy) and this survey.]
    1. Wagner, N.R. ``Searching for public-key cryptosystems," Proceedings of the 1984 Symposium on Security and Privacy, IEEE Computer Society, pp. 91-98. [This article was superseded by the following article.]
    2. Wagner, N.R. and Magyarik, M.R., ``A public-key cryptosystem based on the word problem," Advances in Cryptology: Proceedings of Crypto 84, Lecture Notes in Computer Science No. 196, ed. by G.R. Blakley and D. Chaum, Springer Verlag, pp. 19-36. PDF copy.

    Fingerprinting -- on data and in a database. [Here also a large number of articles have references to the two publications below.]
    1. Wagner, N.R. ``Fingerprinting," Proceedings of the 1983 Symposium on Security and Privacy, IEEE Computer Society, pp. 18-22. PDF copy.
    2. Wagner, N.R., Fountain, R. L., and Hazy, R.J., ``The fingerprinted database," Sixth International Conference on Data Engineering: Proceedings, IEEE Computer Society Press, 1990, pp. 330-336. PDF copy.

    Captchas or Reverse Turing Tests. [This is software that distinguishes between a human and a software agent. See Captchas for my work in this area.]
    1. Wagner, N.R. ``CAPTCHAs and information hiding," Unpublished article, 5 pages. PDF copy.
    2. Wagner, N.R. ``Hiding information from machines," CIAS Express, Jan/Feb 2005, p. 4. JPG copy.

    Chaos-based random number generation, using the Logistic Equation. [This paper gives several refinements in the use of the Logistic Equation to create what appears to be a good RNG.]
    1. Wagner, N.R., ``The logistic lattice in random number generation,'' Proceedings of the Thirtieth Annual Allerton Conference on Communications, Control, and Computing, Coordinated Science Lab and Department of Electrical and Computer Engineering, University of Illinois at Urbabn-Champaign, 1993, pp. 922-931. PDF copy. (See also remarks on the article and The Laws of Cryptography, Chapter 17, pages 106-111, 266-269.)

    Other Computer Science.
    1. Wagner, N.R. ``A Fortran preprocessor for the large program environment," SIGPLAN Notices, Vol. 15 (1980), No. 12, pp. 92-103. PDF copy.
    2. Müller-Schloer, C. and Wagner, N.R. ``The implementation of a cryptography-based secure office system," AFIPS Conference Proceedings: 1982 National Computer Conference (Houston, Texas), AFIPS Press, pp. 487-492. PDF copy.
    3. Wagner, N.R. ``Shared database access using composed encryption functions," Proceedings of the 1982 Symposium on Security and Privacy, IEEE Computer Society, pp. 104-110. PDF copy.
    4. Müller-Schloer, C. and Wagner, N.R. ``Cryptographic protection of personal data cards," Advances in Cryptology: Proceedings of Crypto 82, ed. by D. Chaum et al., Plenum Press, 1983, pp. 219-229.
    5. Wagner, N.R., Putter, P.S., and Cain, M.R., ``Using algorithms as keys in cryptosystems," Proceedings of Eurocrypt 85, Lecture Notes in Computer Science No. 219, ed. by F. Pichler, Springer Verlag, pp. 149-155. PDF copy.
    6. Putter, P.S., and Wagner, N.R. ``Technical Correspondence" (related to the article ``Pass Algorithms: A User Validation Scheme Based on Knowledge of Secret Algorithms"), Communications of the ACM, Vol. 28 (July, 1985), No. 8, p. 750. PDF copy.
    7. Wagner, N.R., ``Technical Correspondence" (related to the article ``Novel Security Techniques for On-line Systems"), Communications of the ACM, Vol. 29 (1986), No. 12, pp. 1240-1241.
    8. Wagner, N.R., Putter, P.S., and Cain, M.R., ``Encrypted database design: Specialized approaches," Proceedings of the 1986 Symposium on Security and Privacy, IEEE Computer Society, pp. 148-153. PDF copy.
    9. Wagner, N.R., Putter, P.S., and Cain, M.R., ``Large scale randomization techniques in cryptography," Advances in Cryptology--Crypto 86, Lecture Notes in Computer Science No. 263, Springer Verlag, 1986, pp. 393-404. PDF copy.
    10. Wagner, N.R., and Putter, P.S., ``Error detecting decimal digits," Communications of the ACM, Vol. 32, No. 1 (Jan., 1989), pp. 106-110. PDF copy,  Review (PDF),  Follow up Technical Correspondence1,  Follow up Technical Correspondence2.
    11. Robbins, K.A., Wagner, N.R., and Wenzel, D.J., ``Virtual rings: an introduction to concurrency," SIGCSE Bulletin, Vol. 21, No. 2 (June, 1989), pp. 23-28, PDF copy.
    12. Wagner, N.R., and Putter, P.S., ``Authors' Response" to ``Technical Correspondence" (related to the article ``Error detecting decimal digits"), Communications of the ACM, Vol. 32 (1989), No. 9, pp. 1132.
    13. Wagner, N.R., ``Randomized fault-detecting leader election in a bi-directional ring," Proceedings of the Second Annual IEEE Symposium on Parallel & Distributed Processing, IEEE Computer Society Press, 1990, pp. 506-510. PDF copy.
    14. Wagner, N.R., ``Correction Terms for Series,'' intended for the College Mathematics Journal of the Mathematical Association of America, but I never bothered sending it in (their standards are pretty high). PDF copy.