This list contains only a small selection of sites about cryptography within the Internet. Further links are contained within the online help of CrypTool and within the script delivered with CrypTool. We appreciate your advice on further interesting links.

Primes, Number Theory and Cryptology (Links and Books)

Web sites

• Kryptologikum - The Kryptologikum is a collection of KIT with many historical exhibits in display cabinets, plus many hands-on experiments, where everyone can learn in a playful way about the principles of modern cryptography. The collection is exhibited regularly.
  http://kryptologikum.de/index.html
• Emma's blog with a 1-page overview about crypto resources. This blog at Norton360Online is educational, and avoids -- to our knowledge -- any 'marketing'.
  http://www.norton360online.com/security-center/cryptography-resource-guide.html
• Website with nearly all in the GDR used codes and encrytion mechanisms -- (only German)
  http://scz.bplaced.net
• Good reading introductionary paper by Scott Aaronson: "The Prime Facts: From Euclid to AKS"
  http://www.scottaaronson.com/writings/prime.pdf
• The Prime Pages by Chris Caldwell
  http://www.utm.edu/research/primes/
• GIMPS (Great Internet Mersenne-Prime Search)
  http://www.mersenne.org/
• Educational project: "Zahlentheorie in der Schule -- Von Primzahlen zur Verschlüsselung mit RSA" -- (German only)
  http://www.hydrargyrum.de/kryptographie
• The Mathematical Atlas (index using mathematics subject classification), Number Theory
  http://www.math.niu.edu/~rusin/known-math/index/11-XX.html
• +Plus, an internet magazine produced by the Millennium Mathematics Project at the University of Cambridge
  http://plus.maths.org
• Randall K. Nichols (Lanaki): "Classical Cryptography Course vol 1+2", 1995
  http://www.apprendre-en-ligne.net/crypto/bibliotheque/lanaki/lesson1.htm
• John Savard: "A Cryptographic Compendium"
  This web site features an extensive section concerning cryptography, especially about Rijndael. Website seemingly no longer updated since 1999.
  http://www.quadibloc.com/crypto/jscrypt.htm
• An Interactive Introduction to Elliptic Curve Cryptography in 6 lessons using the computer algebra system SageMath, by Maike Massierer
  http://webloria.loria.fr/%7Emmassier/ecc-notebook/
• Wonderful Cryptography - topics for a motivational 'Introduction to Cryptography', lecture by Eran Tromer
  http://www.tromer.org/wondercrypt
• Gary C. Kessler: "An Overview of Cryptography"
  Modern and practical paper explaining the concepts behind basic cryptographic methods and providing some real examples.
  http://www.garykessler.net/library/crypto.html

Books

• Craig P. Bauer: "Secret History: The Story of Cryptology", 1st edition, 2013, CRC Press.
• Johannes Buchmann: "Introduction to Cryptography", 2nd ed, 2004, Springer.
• Claudia Eckert: "IT-Sicherheit Konzepte - Verfahren - Protokolle", 7th edition, 2012, Oldenbourg -- (German only)
  http://www.oldenbourg-verlag.de/en/wissenschaftsverlag/it-sicherheit/9783486706871
• Bernhard Esslinger et al.: "Kryptologie für Jedermann", SAP pocket seminar produced within the governmental initiative "Deutschland - Sicher im Netz", 2007 -- (German only)
  https://www.cryptool.org/images/ctp/documents/fibel_kryptologie.pdf
• Keith M. Martin: "Everyday Cryptography -- Fundamental Principles and Applications", March 2012, Oxford University Press
• Alfred J. Menezes, Paul C. van Oorschot and Scott A. Vanstone: "Handbook of Applied Cryptography", 1997, CRC Press
  http://www.cacr.math.uwaterloo.ca/hac/index.html
• Rolf Oppliger: "Contemporary Cryptography, Second Edition", 2011, Artech House
  http://books.esecurity.ch/cryptography2e.html
• Christof Paar and Jan Pelzl: "Understanding Cryptography – A Textbook for Students and Practioners", December 2009, Springer
  This is pedagogically one of the best crypto books currently available. It describes all crypto schemes of practical relevance while avoiding to be shallow. The companion website has extensive PowerPoint slides for teachers, links to further information and videos of 28 lecturers (in German only).
  http://www.crypto-textbook.com/
• Klaus Schmeh: "Kryptografie – Verfahren, Protokolle, Infrastrukturen", 6th edition, 2016, dpunkt -- (German only).
  This is a comprehensive and easy to read book.
• Klaus Schmeh: "Codeknacker gegen Codemacher. Die faszinierende Geschichte der Verschlüsselung", 2nd edition, 2007, W3L -- (German only)
  This is most current among the books dealing in a comprehensive manner with the history of cryptology. It contains a small collection of solved and unsolved crypto riddles.
• Victor Shoup: "A Computational Introduction to Number Theory and Algebra", Second Edition, 2008, Cambridge University Press
  http://shoup.net/ntb/
• William Stallings: "Cryptography and Network Security", 2006, Prentice Hall
  http://williamstallings.com/
• Mark Stamp and Richard M. Low: "Applied Cryptanalysis: Breaking Ciphers in the Real World", 2007, Wiley-Interscience
  The according website has a lot of powerpoint slides and challenge problems.
  http://cs.sjsu.edu/faculty/stamp/crypto/
• Mark Stamp: "Information Security: Principles and Practice", 2nd edition, 2011, Wiley
  It is a comprehensive book divided into four main themes Cryptography, Access Control, Protocols, and Software. Throughout the book the author included frequent "humorous" footnotes. The according website offers a wealth of additional, free material: http://www.cs.sjsu.edu/~stamp/infosec

Comprehensive Link Lists

• Cryptography and Security by Ron Rivest (website seemingly no longer updated)
  http://theory.lcs.mit.edu/~rivest/crypto-security.html
• The PKI page by Stefan Kelm
  http://www.pki-page.info/
• Simon Singh's Webpage, author of "The Codebook"
  http://www.simonsingh.net/cryptography/

Crypto History

• Links and books see here.

Further Information

• heise Security UK - computer security news, information and services
  http://www.heise-security.co.uk/
• German federal ministries page about Internet security -- (German only)
  https://www.bsi-fuer-buerger.de
• Computer Security Resource Center and AES page at NIST
  http://www.nist.gov
• Cryptome archives
  http://cryptome.org/
• ACA (The American Cryptogram Association) is dedicated to promoting the hobby and art of cryptanalysis. You have to become a member (subscription) to get the 2-monthly issue of "The Cryptogram".
  http://www.cryptogram.org/
• Dirk Rijmenants' Cipher Machines and Cryptology
  Historical and technical information about WW2 crypto machines and some nice according free software simulators.
  http://users.telenet.be/d.rijmenants/index.htm
• Geoff's Crypto page
  A page under (permanent) construction with WW2 crypto messages and historic cipher machine simulators.
  http://www.hut-six.co.uk/
• An interestingly designed program (incl. Java source code), which implemented the classic cipher of the Turning Grille
  http://www.turning-grille.com
• A web site with many classic ciphers implemented in PHP -- (German only)
  http://www.kryptographiespielplatz.de/
  
• A web site with a concise summary of the basics of cryptography and cryptanalysis. In addition there is also a glossary and a list of influential figures in the field of cryptography. -- (German only)
  http://www.kryptowissen.de/
  
• CryptoCrack -- A Windows program for solving a whole bunch of classical ciphers with various options.
  https://sites.google.com/site/cryptocrackprogram

Reference to Further Publications about CrypTool

• See "Coverage in Print Media"
• Jamie Kendall (University of Portsmouth): "Cryptographic Techniques for Network Security using CrypTool", April 2008, 91 pages
  This project educates students in the basics of the field of classic and modern cryptography and the according cryptanalysis. The project explores the software CrypTool 1 extensively and comprises of a set of three one hour lab sheets as well as an accompanying report with the solutions.
• CrypTool 2 at CeBIT 2010
  The University of Duisburg-Essen presented CrypTool 2 as e-learning platform, peers@play and the combination of both for distributed modern cryptanalysis.
• 15th Colloquium for infomation Systems Security Education Fairborn, Rong Yang, Layne Wallace, and Ian Burchett: "Teaching Cryptology At All Levels Using CrypTool", June 2011
  [Abstract - This paper introduces cryptology in the framework of general cybersecurity and advocates that it is an appropriate mechanism for introducing security issues into the classroom at all level of the curriculum. A practical free software package called CrypTool which can be a major asset in any attempt to teach cryptology to a range of student audiences is presented. Applications and classroom experiences using CrypTool are discussed along with some student feedback.]
• 7th International Conference on Education and Information Systems, Technologies and Applications (EISTA 2012), Reducing the complexity of understanding cryptology using CrypTool, July 2012
  [Abstract - Cryptography and cryptanalysis are characterized by a great number of algorithms, parameters, and protocols where at least some of them can be considered as complex mathematical structures. In this paper, electronic learning such as self-regulated learning, computer-based trainings, and learning by doing are presented with the help of a modern e-learning program – CrypTool (CT) – which supports these approaches for developers and users. Additionally, this paper fortifies these claims with an evaluation using the feedback from classes where CT was used to teach cryptographic algorithms. EISTA 2012 was part of the 6th International Multi-Conference on Society, Cybernetics and Informatics (IMSCI 2012).]
• Sasa Adamovic, Marko Sarac, Mladen Veinovic, Milan Milosavljevic, and Aleksandar Jevremovic: An Interactive and Collaborative Approach to Teaching Cryptology, 2013, Journal of Educational Technology & Society (Vol. 17, Issue 1)
  [Abstract - This paper describes the implementation of a novel module for the CT2 educational software that provides the ability to communicate over the local computer network and the Internet from within CT2. The solution is used to let students interactively and collaboratively work on solving cryptologic problems. The approach tested in the classroom setting was evaluated and leads to better final grades and an increase in students' interest for this area.]

Coverage in Online Media

• Telepolis, Werkzeugkasten für Codeknacker, August 2008 (German)
• University award of Koblenz
  Teaching post student won University award of Koblenz with his work about CrypTool 2.
• http://en.wikipedia.org/wiki/CrypTool