Historical Ciphers Part 2

Total Page:16

File Type:pdf, Size:1020Kb

Historical Ciphers Part 2 ECE 646 - Lecture 7 Required Reading • W. Stallings, Cryptography and Network Security, Historical Ciphers Chapter 3, Classical Encryption Techniques Part 2 • A. Menezes et al., Handbook of Applied Cryptography, Chapter 7.3 Classical ciphers and historical development 1 2 14 Substitution Ciphers (2) 12 Character frequency 2. Polyalphabetic substitution cipher 10 in a long English 8 plaintext M = m1 m2 … md 6 m m … m d+1 d+2 2d 4 m2d+1 m2d+2 … m3d 2 ….. 0 a b c d e f g h i j k l m n o p q r s t u v w x y z C = f1(m1) f2(m2) … fd(md) Character frequency 14 in the corresponding f1(md+1) f2(md+2) … fd(m2d ) 12 ciphertext f1(m2d+1 ) f2( m2d+2) … fd(m3d ) 10 for a polyalphabetic ….. 8 substitution cipher d is a period of the cipher 6 1 4 × 100% » 3.8 % Key = d, f1, f2, …, fd 26 2 d 26 d Number of keys for a given period d = (26!) » (4 × 10 ) 0 a b c d e f g h i j k l m n o p q r s t u v w x y z 3 4 1 Polyalphabetic substitution ciphers Vigenère Cipher - Example Simplifications (1) Plaintext: TO BE OR NOT TO BE A. Vigenère cipher: polyalphabetic shift cipher Key: NSA Invented in 1568 Encryption: T O B E O R ci = fi mod d(mi) = mi + ki mod d mod 26 N O T T O B -1 mi = f i mod d(ci) = ci - ki mod d mod 26 E Key = k0, k1, … , kd-1 Number of keys for a given period d = (26)d 5 6 Vigenère Square Vigenère Square plaintext: a b c d e f g h i j k l m n o p q r s t u v w x y z plaintext: a b c d e f g h i j k l m n o p q r s t u v w x y z 3 a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a N S A c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c T O B e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e E O R g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g N O T i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h T O B j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j E l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l G G B 1 n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n R G R p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p A G T r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q G G B 2 s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s R u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u w x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v x y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w y z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x z a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g h i j k l m n o p q r s t u v w x y 7 8 2 Vigenère Cipher - Example Determining the period of the polyalphabetic cipher ’ Plaintext: TO BE OR NOT TO BE Kasiski s method Key: NSA N S A Ciphertext: G G B R G R A G T G G B R Encryption: T O B E O R N O T Distance = 9 T O B E Period d is a divisor of the distance between G G B identical blocks of the ciphertext R G R A G T G G B In our example: d = 3 or 9 R Ciphertext: GGBRGRAGTGGBR 9 10 Index of coincidence method (1) Index of coincidence method (2) ni - number of occurances of the letter i in the ciphertext Measure of roughness: i = a .
Recommended publications
  • To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology?
    Portland State University PDXScholar Young Historians Conference Young Historians Conference 2016 Apr 28th, 9:00 AM - 10:15 AM To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology? Hayley A. LeBlanc Sunset High School Follow this and additional works at: https://pdxscholar.library.pdx.edu/younghistorians Part of the European History Commons, and the History of Science, Technology, and Medicine Commons Let us know how access to this document benefits ou.y LeBlanc, Hayley A., "To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology?" (2016). Young Historians Conference. 1. https://pdxscholar.library.pdx.edu/younghistorians/2016/oralpres/1 This Event is brought to you for free and open access. It has been accepted for inclusion in Young Historians Conference by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. To what extent did British advancements in cryptanalysis during World War 2 influence the development of computer technology? Hayley LeBlanc 1936 words 1 Table of Contents Section A: Plan of Investigation…………………………………………………………………..3 Section B: Summary of Evidence………………………………………………………………....4 Section C: Evaluation of Sources…………………………………………………………………6 Section D: Analysis………………………………………………………………………………..7 Section E: Conclusion……………………………………………………………………………10 Section F: List of Sources………………………………………………………………………..11 Appendix A: Explanation of the Enigma Machine……………………………………….……...13 Appendix B: Glossary of Cryptology Terms.…………………………………………………....16 2 Section A: Plan of Investigation This investigation will focus on the advancements made in the field of computing by British codebreakers working on German ciphers during World War 2 (1939­1945).
    [Show full text]
  • This Story Begins Sometime in the Early 1930S, When the Poles And
    XYZ Prof. Włodzimierz Zawadzki Institute of Physics, Polish Academy of Sciences [email protected] Mathematicians are important, and not just in wartime. his story begins sometime in the early 1930s, developing programmable computers. Knox informed when the Poles and the French first took an Turing about the progress made by the Poles, and Tur- T interest in breaking the code generated by the ing built a sophisticated machine of his own that was Enigma encryption machines. The Enigma was a Ger- capable of cracking the increasingly complex Wehr- man-made electro-mechanical device that looked a bit macht codes. In a nod to the Polish pioneers, Turing like a typewriter with little lights, and prior to WWII too called his device “the bomb.” Despite the urgings they were available commercially. The decision to of British intelligence, Bertrand was reluctant to get crack the Enigma code proved far-sighted when the the Polish team out of Nazi-occupied France and into machines underwent a complex and classified rede- Bletchley Park. The team ended up in southern France sign for military purposes in the run-up to the war. and, at one point, in North Africa. Despite their con- Codebreaking challenges had earlier been handled tinuing insights, the Polish team’s direct contribution by linguists, but the Enigma’s rotor-encrypted codes to the breaking of the Enigma code diminished. required codebreakers with a mathematical back- When the United States joined the war, one of the ground. The Polish Cipher Bureau, an intelligence out- most difficult aspects of Enigma decryption focused fit located near Warsaw, set up a task force consisting on the communications of the German U-boat fleet, of Marian Rejewski, Henryk Zygalski and Jerzy Róży- which harassed American supply convoys crossing cki.
    [Show full text]
  • Historical Ciphers • A
    ECE 646 - Lecture 6 Required Reading • W. Stallings, Cryptography and Network Security, Chapter 2, Classical Encryption Techniques Historical Ciphers • A. Menezes et al., Handbook of Applied Cryptography, Chapter 7.3 Classical ciphers and historical development Why (not) to study historical ciphers? Secret Writing AGAINST FOR Steganography Cryptography (hidden messages) (encrypted messages) Not similar to Basic components became modern ciphers a part of modern ciphers Under special circumstances modern ciphers can be Substitution Transposition Long abandoned Ciphers reduced to historical ciphers Transformations (change the order Influence on world events of letters) Codes Substitution The only ciphers you Ciphers can break! (replace words) (replace letters) Selected world events affected by cryptology Mary, Queen of Scots 1586 - trial of Mary Queen of Scots - substitution cipher • Scottish Queen, a cousin of Elisabeth I of England • Forced to flee Scotland by uprising against 1917 - Zimmermann telegram, America enters World War I her and her husband • Treated as a candidate to the throne of England by many British Catholics unhappy about 1939-1945 Battle of England, Battle of Atlantic, D-day - a reign of Elisabeth I, a Protestant ENIGMA machine cipher • Imprisoned by Elisabeth for 19 years • Involved in several plots to assassinate Elisabeth 1944 – world’s first computer, Colossus - • Put on trial for treason by a court of about German Lorenz machine cipher 40 noblemen, including Catholics, after being implicated in the Babington Plot by her own 1950s – operation Venona – breaking ciphers of soviet spies letters sent from prison to her co-conspirators stealing secrets of the U.S. atomic bomb in the encrypted form – one-time pad 1 Mary, Queen of Scots – cont.
    [Show full text]
  • The Enigma History and Mathematics
    The Enigma History and Mathematics by Stephanie Faint A thesis presented to the University of Waterloo in fulfilment of the thesis requirement for the degree of Master of Mathematics m Pure Mathematics Waterloo, Ontario, Canada, 1999 @Stephanie Faint 1999 I hereby declare that I am the sole author of this thesis. I authorize the University of Waterloo to lend this thesis to other institutions or individuals for the purpose of scholarly research. I further authorize the University of Waterloo to reproduce this thesis by pho­ tocopying or by other means, in total or in part, at the request of other institutions or individuals for the purpose of scholarly research. 11 The University of Waterloo requires the signatures of all persons using or pho­ tocopying this thesis. Please sign below, and give address and date. ill Abstract In this thesis we look at 'the solution to the German code machine, the Enigma machine. This solution was originally found by Polish cryptologists. We look at the solution from a historical perspective, but most importantly, from a mathematical point of view. Although there are no complete records of the Polish solution, we try to reconstruct what was done, sometimes filling in blanks, and sometimes finding a more mathematical way than was originally found. We also look at whether the solution would have been possible without the help of information obtained from a German spy. IV Acknowledgements I would like to thank all of the people who helped me write this thesis, and who encouraged me to keep going with it. In particular, I would like to thank my friends and fellow grad students for their support, especially Nico Spronk and Philippe Larocque for their help with latex.
    [Show full text]
  • I Islander Readers I Say the Damdest I Things... 7A ARTS » LEISURE: Life's
    mm ARTS » LEISURE: EVERY WEEK: i Islander readers Life's a beach 1B Calendar 27A I say the damdest Ostrich eggs, . Classifieds 18C i things... 7A anyone? 4B Island map 25A 1961-1986 Still first after 25 years VOL. 26, NO. 13 TUESDAY, MARCH 3>, 1987 THREE SECTIONS, 76 PAGES 50 CENTS Who's the wiser? Michael Welngart, staff member at Care and ed howl back in Its nest on Captiva last weekend. The strong winds last week. Story on page 1C. Photo by Rehabilitation of Wildlife, placed this baby great horn- owl was one of two that was blown from the nest by Rlcki Kosakow Cooper. INDEX2 •-,•.•. ALSO THIS WEEK How do you Executive women Westall isn't discouraged Arts-Leisure 4B organize new chapter when osprey parents Brldae 13B combine computers Club news 14B with seashells? of service club on Sanibel vent their indignation Fishing tips 10C Long-time Island, shellers President Kappy King Cole in- In his first osprey chick banding Nature programs 3C Margaret Thorsen and Ede vites interested Island business expedition of the season, Mark Obituary 15A Mugridge have found a way - and women to learn more about the "Bird" Westall suffered minor in- juries to his arm when an angry Police beat 4A their efforts will benefit the Sanibel fledgling Sanibel-Captiva Zonta Club. osprey mother dove at him. Shelling tips 11C Shell Museum and Research Foundation. 23B 10A The ISLANDER Tuesday, March 31, 1987 3A City hopes to gain endorsement of Realtors Tuesday for sales tax to help purchase sensitive wetlands 2A Island Shorts March 31,1987 By BARBARA BRUNDAGE directors, as do city councilmen, view a recreational facilities would not be inherent obligation and responsibility Islander staff writer real estate transaction tax as the most included.
    [Show full text]
  • %E Morse Magazine
    1'£um6er 23 - f£aster 1992 ... %e Morse. Magazine.. - MORSUM MAGNIFICAT was [lTst published in Holland, in 1983, by the late Rinus Helkmons PAOBFN. Now published in Britain, it aims to provide international coverage of all aspects of Morse telegraphy, past present and future. MORSUM MAGNIFICAT is for all Morse enthusiasts, amateur or professional, active or retired. It brings together material which would otherwise be lost to posterity, providing an invaluable source of interest, reference and record relating to the traditions and practice of Morse. SUBSCRIPTIONS: For one year (four issues) United Kingdom: £8.50 per annwn, post-paid Europe, including Eire: £8.50 sterling Other countries: Surface mail- £9.00 sterling (or US $17.00 cash only) Ainnail- £11.00 sterling (or US $21.00 cash only) Cheques payable to 'G C Arnold Partners'. Payment by Access, Eurocard, Master­ card or Visa is also accepted; quote your card nwnber and expiry date. Please note that, owing to very high bank charges for currency exchange, we are unable to accept overseas cheques, drafts, money orders, etc., unless payable in sterling. Overseas cheques and drafts must be drawn on a London clearing bank. EDITORIAL AND SUBSCRIPTION OmCES: Morswn Magnificat. 9 Wetherby Close, Broadstone, Dorset BH18 8JB, England Telephone: Broadstone (0202) 658474; International +44 202658474 EDITOR Geoff Arnold G3GSR CONSULTANT EDITOR Tony Smith G4FAI, 1 Tash Place, London NIl IPA, England. Tel: 081-3684588 © G C Arnold Partners 1992 ISSN 0953-6426 Printed by Hertfordshire Display Company, Ware, Herts. ON OUR FRONT COVER A GNT Undulator in working condition. Photo by Dennis Goacher G3L1.Z Contents IRST OF ALL, AN APOLOOY to all of you 2 News F who were confused by the fact that they hadn't 6 Clandestine Radio - 2 had a ChrisbnaS issue of MM.
    [Show full text]
  • Historical Ciphers
    ECE 646 - Lecture 6 Historical Ciphers Required Reading • W. Stallings, Cryptography and Network Security, Chapter 2, Classical Encryption Techniques • A. Menezes et al., Handbook of Applied Cryptography, Chapter 7.3 Classical ciphers and historical development 1 Why (not) to study historical ciphers? AGAINST FOR Not similar to Basic components became modern ciphers a part of modern ciphers Under special circumstances Long abandoned modern ciphers can be reduced to historical ciphers Influence on world events The only ciphers you can break! Secret Writing Steganography Cryptography (hidden messages) (encrypted messages) Substitution Transposition Transformations Ciphers (change the order of letters) Codes Substitution Ciphers (replace words) (replace letters) 2 Selected world events affected by cryptology 1586 - trial of Mary Queen of Scots - substitution cipher 1917 - Zimmermann telegram, America enters World War I 1939-1945 Battle of England, Battle of Atlantic, D-day - ENIGMA machine cipher 1944 – world’s first computer, Colossus - German Lorenz machine cipher 1950s – operation Venona – breaking ciphers of soviet spies stealing secrets of the U.S. atomic bomb – one-time pad Mary, Queen of Scots • Scottish Queen, a cousin of Elisabeth I of England • Forced to flee Scotland by uprising against her and her husband • Treated as a candidate to the throne of England by many British Catholics unhappy about a reign of Elisabeth I, a Protestant • Imprisoned by Elisabeth for 19 years • Involved in several plots to assassinate Elisabeth • Put on trial for treason by a court of about 40 noblemen, including Catholics, after being implicated in the Babington Plot by her own letters sent from prison to her co-conspirators in the encrypted form 3 Mary, Queen of Scots – cont.
    [Show full text]
  • Island Is a Specially Designed Comrruni'y That Compliments Mturt
    L island REPORTER SANIBBL & CAPTIVA, FLORIDA I Volume Ntmihci Dale Li E ANDCAPTIVA FLORIDA* February 7 1985 island VOLJWE U *• MBEfl 3 J 'Sanibel is not a destination xm shopping area' --CITYCGUMCIL tebn tfV ? I'A'JT I \Jn6 K< potii the island eye Ancient art of Chinese great dates SUuU its m hanne layering \to >d s Itrst grade class nt S iwbtl February \ earn the meienl htcmentaru SIAJU/ art of Chincst lajtr en crrunicttnq Hi'thdaj of John l)t< re ll-thrum 7 ing r ich Wedmsdij clrstroum cientiand at 10 am there will 7 1804 May 17 18861 *mcri<an invtntnr iir/iu'it* in The til a hinds oh and manufacturer of the strel plow demonstration of the tirsl Grade Star Bov Scout*, pav commemorates thf imor prop igalion Itchni The >.t~drnt* art quc of air leering in dtiutnl into 8 porahon of thr Boy Scout's ol \iunc i < n use for more than reporters and lebruarj 8 1910 A Hoy Scout* of •I 000 Years in China photagrapbtrv u\th American Sabbath is u-suallj ichtdulid Eviryone will havt <* some dictating for Sunday near this dtte Hoj Scouts chance to tr% the stunes aidotners Dav is scheduled annually near thr date technique draj ing pictures of I he organisations founding and it The Students kai" followed by week or month long ac Bring your pocket htcn lery eiaud lt knife to the Sin.bcl abnul it, $ayt Mrs B rthday of Am> Lo-*ell (Fthruary *» Captiva Conservation Wood n ho periodical Foundations Native 1874 May 12 1825) Amenm pod ly runs off Ike paper Plant Nursery each biographer, and critic, a leader among thi or the school Wednesday says imagist poet* authorofatnonumi ntul life manager Dee Serage ofKtats For more inforantion nil 472 1932 or Birthday of Boris I eonidouch Pistirmk 172 2329 10 (tebruarj 10 1890 Ma> 10 l«60l Russian A donitton of S5 is P<« i novrlist and translator who «a«- awirdrd thr 1985 >obil 1'n/f in htera t ire hul » a* forced to refuse it hi just {f Bring your | ditKalipp sition the author of D <l r wild harvest 1 1 Ilirthdav «>f Thomas Uu tdi=<n 1 1 IFdruarj 11 1&17 Octobt-r 1b 1 *• il Do sou ft.
    [Show full text]
  • Revised Edition 2019 Dedicated to the Memory of the Allied Polish Cryptanalysts
    The Cryptographic Mathematics of ⒺⓃⒾⒼⓂⒶ This publication presents a historical perspective for informational and educational purposes, is the result of independent research, and does not necessarily reflect a position of NSA/CSS or any other US government entity. This publication is distributed free by the National Security Agency. If you would like additional copies, please email your request to [email protected] or write to: Center for Cryptologic History National Security Agency 9800 Savage Road, Suite 6886 Fort George G. Meade, MD 20755 Color photographs, David S. Reynolds, NSA/CSS photographer Cover: General Heinz Guderian in armored command vehicle with an Engima machine in use, May/June 1940. German Federal Archive The Cryptographic Mathematics of Enigma Dr. A. Ray Miller Center for Cryptologic History National Security Agency Revised edition 2019 Dedicated to the Memory of the Allied Polish Cryptanalysts Marian Rejewski Jerzy Rozycki Henryk Zygalski he Enigma cipher machine had the confidence of German forces who depended upon its security. This misplaced con- Tfidence was due in part to the large key space the machine provided. This brochure derives for the first time the exact number of theoretical cryptographic key settings and machine configura- tions for the Enigma cipher machine. It also calculates the number of practical key settings Allied cryptanalysts were faced with daily throughout World War II. Finally, it shows the relative contribution each component of the Enigma added to the overall strength of the machine. ULTRA [decrypted Enigma messages] was the great- est secret of World War II after the atom bomb. With the exception of knowledge about that weapon and the prob- able exception of the time and place of major operations, such as the Normandy invasion, no information was held more tightly….
    [Show full text]
  • Enigma, Les Décrypteurs Polonais Et Les Services Secrets Français, 1932–1945
    ZESZYTY NAUKOWE UNIWERSYTETU JAGIELLOŃSKIEGO Prace Historyczne 146, z. 1 (2019), s. 209–217 doi:10.4467/20844069PH.19.011.9575 www.ejournals.eu/Prace-Historyczne ENIGMA, LES DÉCRYPTEURS POLONAIS ET LES SERVICES SECRETS FRANÇAIS, 1932–1945 http://orcid.org/0000-0002-5623-571X Jean-Charles Foucrier Université Paris-Sorbonne – Paris IV ABSTRACT ENIGMA, THE POLISH CODEBREAKERS AND THE FRENCH SECRET SERVICE, 1932–1945 In the early 1930’s, the Polish codebreakers succeeded while all the others failed: they broke the Enigma. Three young and brilliant mathematicians, Marian Rejewski, Henryk Zygalski and Jerzy Różycki managed to read the German cyphertexts from 1933 to as late as 1939. But this huge suc- cess remained a secret for a long time, unknown in France and England. After the fall of Poland in September 1939, the three mathematicians linked their fate with the French secret service and kept breaking the Enigma code. Again, following the French defeat of June 1940, they experienced exile and irremediably sank into oblivion. Today, the story of the Polish codebreakers and the French secret service remains very little known in France, although their work proved decisive in the Allied victory during the Second World War. Key words: World War II, Enigma, codebreaking, secret service. Słowa kluczowe: II wojna światowa, Enigma, łamanie szyfru, tajne służby. Août 1932. Trois jeunes Polonais s’engouff rent dans le vaste Palais Saxon de Var- sovie (Pałac Saski), siège du Bureau du Chiff re (Biuro Szyfrów). Marian Rejewski, Henryk Zygalski et Jerzy Różycki représentent l’élite des mathématiciens polonais, fraîchement diplômés de l’Université Adam Mickiewicz de Poznań.
    [Show full text]
  • Breaking Enigma Samantha Briasco-Stewart, Kathryn Hendrickson, and Jeremy Wright
    Breaking Enigma Samantha Briasco-Stewart, Kathryn Hendrickson, and Jeremy Wright 1 Introduction 2 2 The Enigma Machine 2 2.1 Encryption and Decryption Process 3 2.2 Enigma Weaknesses 4 2.2.1 Encrypting the Key Twice 4 2.2.2 Cillies 5 2.2.3 The Enigma Machine Itself 5 3 Zygalski Sheets 6 3.1 Using Zygalski Sheets 6 3.2 Programmatic Replication 7 3.3 Weaknesses/Problems 7 4 The Bombe 8 4.1 The Bombe In Code 10 4.1.1 Making Menus 10 4.1.2 Running Menus through the Bombe 10 4.1.3 Checking Stops 11 4.1.4 Creating Messages 11 4.1.5 Automating the Process 11 5 Conclusion 13 References 14 1 Introduction To keep radio communications secure during World War II, forces on both sides of the war relied on encryption. The main encryption scheme used by the German military for most of World War II employed the use of an Enigma machine. As such, Britain employed a large number of codebreakers and analysts to work towards breaking the Enigma-created codes, using many different methods. In this paper, we lay out information we learned while researching these methods, as well as describe our attempts at programatically recreating two methods: Zygalski sheets and the Bombe. 2 The Enigma Machine The Enigma machine was invented at the end of World War I, by a German engineer named Arthur Scherbius. It was commercially available in the 1920s before being adopted by the German military, among others, around the beginning of World War II.
    [Show full text]
  • CLASSICAL CRYPTOGRAPHY COURSE by LANAKI February 22
    CLASSICAL CRYPTOGRAPHY COURSE BY LANAKI February 22, 1996 Revision 0 COPYRIGHT 1996 ALL RIGHTS RESERVED LECTURE 8 INTRODUCTION TO CRYPTARITHMS AND HILL CIPHER SUMMARY In Lecture 8, we depart from the schedule for a real treat. In the first part of this Lecture, we introduce Cryptarithms by our guest lecturer LEDGE (Dr. Gerhard D. Linz). LEDGE has already produced one of our better references on beginning cryptography [LEDG], and I appreciate his assistance in our course. The cryptarithms portion of this course will be presented in three lectures and for the final book labelled Lectures 20 - 23. Following the Cryptarithms section we introduce the Hill Cipher. Our second guest lecturer is NORTH DECODER. Dr. Jerry Metzger and his team are presenting you with the Crypto Drop Box and the ACA-L Listserver. The Hill cipher has six GIF files associated with it and can be found at the CDB. Waiting in wings patiently for my resource materials is TATTERS to present Cipher Exchange problems. INTRODUCTION TO CRYPTARITHMS (by LEDGE) Here's the first of the Cryptarithm lectures. It consists of a general introduction to the genre including how to read the problems. That's followed by an explanation of modulo arithmetic. Then we look at how to identify the letters that represent 0, 1 and 9, called digital characteristics. Then there are two sections on making inferences, each demonstrating a problem solution. Finally, there's a section on extracting square roots. Next lecture LEDGE will give some aids for solving multiplication problems and then go into base 11 and base 12 arithmetic.
    [Show full text]