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1.
LOUIS KRUH 《Cryptologia》2013,37(2):126-127
AbstractFialka M-125 (sometimes called the “Russian Enigma”) is an electro-mechanical rotor cipher machine used during the Cold War. The designers of this cipher eliminated the known weaknesses of Enigma. In this article, the authors summarize the main principle of the Fialka algorithm from public sources. Moreover, they introduce a mathematical model of the Fialka cipher, and they analyse the effect of blocking pin settings on the cipher's period. 相似文献
2.
John Lawrence 《Cryptologia》2013,37(4):343-366
We prove a generalization of a theorem of Rejewski. This theorem shows how one can solve an equation of the form XY=α in a symmetric group, where α is a given permutation and X and Y are each of order two with a specified number of disjoint transpositions. The number of solutions is also part of the theorem. Using this theorem we outline what we believe was the Polish solution (or very close to it) to the Enigma assuming that one had no data from daily keys. With some assumptions on independence of events, we show that the Polish Cipher Bureau would probably have broken the Enigma in just over four years. 相似文献
3.
Francis A. Raven 《Cryptologia》2013,37(2):104-108
Abstract This article describes the importance of the Knox contribution to the breaking of the plugboard German Enigma through his early work on the commercial machine; as well as his invention of “rodding” and exploitation of the Saga method of “boxing.” It also covers the multi-turnover Abwehr machine through observation of the phenomenon of ‘crabs and lobsters’ in message indicators. 相似文献
4.
ROLAND ANDERSON 《Cryptologia》2013,37(4):348-359
Abstract The Faculty of Mathematics and Computer Science of Adam Mickiewicz University established an annual series of lectures in computer science. The series is named after Marian Rejewski, Jerzy Ró?ycki, and Henryk Zygalski, alumni of the University who played a key role in the Enigma cipher machine breaking. The inaugural lectures were given by Marek Grajek, Adrew Odlyzko, and Józef Pieprzyk on Cryptology Day, January 25th, 2008. 相似文献
5.
During the last few months of 1932, the Polish mathematician Marian Rejewski solved the problem of finding the internal connections of the rotors and reflector of the Enigma cipher machine used by the German army at that time. This allowed the Polish Cipher Bureau to construct an analogue of the machine, and subsequently to find effective methods for deciphering secret messages. Rejewski performed this feat virtually alone using cryptographic material provided by the Polish secret services. His knowledge of the theory of permutation groups was essential in solving this problem.
This article describes in detail how to find the complete wiring of the rotors and reflector of Enigma, as well as other specifics, using data that Rejewski had at his disposal, by systematically presenting the resolution of all cases that could have been encountered. Similarly, we complete those stages of the procedure that were only outlined by Rejewski. 相似文献
6.
Umkehrwalze A was the original reflector used in the version of the Enigma machine employed by the German armed services. Its wiring was originally deduced by the Polish cryptanalyst Marian Rejewski in December 1932 or January 1933, but details of the wiring have not previously been published. Sufficient information to recover the wiring analytically is provided in a wartime document by Alan Turing, and other sources have been found to confirm the solution. This paper presents the wiring, along with alternative methods of recovering it from Turing's data. 相似文献
7.
《国际互联网参考资料服务季刊》2013,18(3-4):149-157
Abstract Linking full-text proprietary databases with Google Scholar revealed three significant limitations in terms of precision (no subject heading search), transparency (no listing of information sources), and visibility (Google Scholar details are hard to find). Google Scholar is not a “one stop shopping” search engine that retrieves all relevant data from a library's licensed content. Despite these shortcomings, Google Scholar is a worthwhile search option for students, which may steer them away from Web resources, and towards the library's catalog and databases. 相似文献
8.
John Wright 《Cryptologia》2018,42(3):222-226
In 1932, Marian Rejewski, who was a young mathematician working at the Polish Cipher Bureau, brilliantly recovered the internal wiring of the military Enigma. His initial efforts were unsuccessful because he assumed that the entry permutation was the same as in the commercial machine. Luckily he tried the identity permutation as an alternative and that proved to be correct. This note describes how Rejewski’s equations may be used to deduce the entry permutation without any guesswork, a technique that was later rediscovered by Alan Turing and by Lieutenant Andrew Gleason. 相似文献
9.
AbstractThis paper examines the output ciphertext sequences produced by an Enigma machine that is keyed repeatedly with the same letter. The number of occurrences of runs (subsequences of successive identical characters) of different lengths is counted, and their statistics are compared with what would be expected for an ideal source of independent, equiprobable random letters from a 25-letter alphabet. Unexpectedly high run counts are found for certain rotor configurations; the “extra” runs are shown to arise from particular features of rotor wiring. 相似文献
10.
WOLFGANG MACHE 《Cryptologia》2013,37(4):230-242
World War II's “Fish” cipher was a British cover word for all kinds of encrypted German radio teleprinter messages. The GC&CS at Bletchley, Buckinghamshire, did not only attack successfully Enigma traffic (Morse signals on radio links) by the electromechanical deciphering machines called BOMBES. In addition, Bletchley's electronic text processor COLOSSUS broke the German “Tunny” ciphers, generated by TELEPRINTER ATTACHMENTS “SZ”, employed by the ‘Heer’ (Army) on HF radio links. 相似文献
11.
David Kahn 《Cryptologia》2013,37(2):121-126
The city of Bydgoszcz, Poland, held a conference on Enigma in honor of Marian Rejewski, one of the 1932 solvers of that cipher machine who was born and brought up in that industrial city. I then visited several sites in Poland connected with cryptology. 相似文献
12.
13.
Daniel J. Girard 《Cryptologia》2016,40(5):428-451
This article gives the solutions of the only four messages known to still exist from the previously unbroken Japanese-German joint naval radio communications traffic in the system known as “Tirpitz,” which used the specially-designed model T Enigma machine. It also explains the methods used by the author to break the messages, and gives some background on the model T Enigma and its usages. 相似文献
14.
Etienne Cocquebert Damien Trentesaux Christian Tahon 《Information and Software Technology》2010,52(12):1272-1285
ContextWebsites are increasingly important for advertising and announcing information and they have become virtual business operations support tools. Thus, website designers have to take an increasing number of criteria (cost, delay, quality, security, maintenance) into account during design process to satisfy the needs.ObjectiveThe objective of this paper was to present our WISDOM method that: guides the designer through the website design process, proposes design solutions based on already existing solutions for online website design, facilitates the choice of software components to implement specific services, and speeds up website construction.MethodThe originality of our method is that it links the design process to formalized experience and a software component characterization that allows both functional and non-functional aspects to be considered.ResultsThis method relies on the state-of-the-art strengths in the website design process, modeling dimensions, Model-Driven Engineering and the patterns approach. We propose an implementation of our method as a dedicated website which helps website design and provides a website analysis catalog and a software component analysis catalog.ConclusionOur analysis of the method’s use highlights that formalizing the steps of the design process helps designers, especially novice designers, to design a website; our analysis of the tool’s use highlights its efficiency for rapid website development and its use of the “website family” concept. The results are so very encouraging for both method and tool; both facilitate website design by reusing existing solutions and components. 相似文献
15.
《国际互联网参考资料服务季刊》2013,18(3):29-43
Abstract Once the decision was made to catalog electronic serials (electronic journals or e-journals) at the University of Pennsylvania, it was up to the serials catalogers to decide how much information would be provided in the record, as well as to develop a “standard” form. Even though the cataloging would come from two separate units (the main University Library and the Biomedical Library), the records would be part of the same OPAC. As very few other libraries were cataloging Internet resources at the time and national standards were still under discussion, it was necessary to “learn by doing.” The authors describe the process of creating cataloging records for the more than 1550 Internet serial resources and the progression from brief, basic records on the library's gopher to full-level cataloging of Internet titles for these items. Examples of problems unique to this format are supplied; discussion of foreign and domestic online newspapers and established publisher-and/or vendor-generated scholarly journals are included. 相似文献
16.
Heidi Williams 《Cryptologia》2013,37(1):4-17
A 1995 article in this journal presented a study by James Gillogly entitled “Ciphertext-Only Cryptanalysis of Enigma” [7, p. 405]. In this paper I will make improvements on Gillogly's techniques by choosing a more effective statistical test and an improved algorithm which allow me to decipher a 500-letter message encrypted by an Enigma machine with 10 plugs. 相似文献
17.
Olaf Ostwald 《Cryptologia》2017,41(5):395-421
“Breaking German Army Ciphers” is the title of a Cryptologia article from 2005, describing the lucky survival of several hundred authentic Enigma messages of World War II, and an account of a ciphertext-only cryptanalysis of a large number of these messages, leaving only a few (mostly short messages) unbroken. After reviewing the work done, and investigating the reasons for both lucky breaks and close misses, the modern ciphertext-only attack on Enigma messages is improved, especially on genuine ones with short lengths and/or many garbles. The difficulties of a proper measure for the candidate’s closeness to a plaintext are clarified. The influence on the decryption process of an empty plugboard and one with only a few correct plugs is examined. The method is extended by a partial exhaustion of the plugboard combined with an optimized hillclimbing strategy. The newly designed software succeeds in breaking formerly unbroken messages. 相似文献
18.
Olaf Ostwald 《Cryptologia》2016,40(1):70-91
The development history of Umkehrwalze Dora, Enigma's pluggable reflector, is presented from the first ideas in the mid-1920s to the last development plans and its actual usage in 1945. An Enigma message in three parts, enciphered with Umkehrwalze Dora and intercepted by the British on 11 March 1945, is shown. The successful recovery of the key of this message is described. Modern computer-based cryptanalysis is used to recover the wiring of the unknown “Uncle Dick,” which the British called this field-rewirable reflector. The attack is based on the known ciphertext and plaintext pair from the first part of the intercept. After recovery of the unknown reflector wiring and the daily key, the plaintext of the second part of the message is revealed. 相似文献
19.
Graham A. Niblo 《Cryptologia》2013,37(3):277-286
Abstract A declassified document confirms that the United States' 1943/4 Bombes continued to be used against the German's Enigma encryption device until at least 1955. 相似文献
20.
Lee A. Gladwin 《Cryptologia》2013,37(1):11-17
Recently declassified documents from the “Crane Collection” at the National Archives (USA) reveal much of the purpose of Alan Turing's visit to the United States during the Winter of 1942–1943. The “Bombe Correspondence” file contains Turing's “Visit To National Cash Register Corporation of Dayton, Ohio” and additional material which places this report and his earlier “Treatise on the Enigma” in the context of his role as consultant to the U. S. Navy Cryptanalytic Section (Op-20-G) on the design of the Navy Bombe and other related matters. The documents in this collection reveal a productive and decisive relationship between Turing and Op-20-G dating from the visit of the Sinkov mission to Bletchley Park in February 1941. 相似文献