Cryptography: New Applications
http://www.maplesoft.com/applications/category.aspx?cid=223
en-us2014 Maplesoft, A Division of Waterloo Maple Inc.Maplesoft Document SystemMon, 28 Jul 2014 16:28:06 GMTMon, 28 Jul 2014 16:28:06 GMTNew applications in the Cryptography categoryhttp://www.mapleprimes.com/images/mapleapps.gifCryptography: New Applications
http://www.maplesoft.com/applications/category.aspx?cid=223
Maple `Keyless` Base b Encryption Scheme
http://www.maplesoft.com/applications/view.aspx?SID=149026&ref=Feed
In this submission it will be shown that the convert/base built-in function can be used to create many new tools which can encrypt or decrypt any file selected. Such a tool, named Maple "keyless` base b encryption scheme, allows to determine the admissible number of elements of the set of ASCII decimals which will be present in the encrypted file, and to choose all the elements of this set.<img src="/applications/images/app_image_blank_lg.jpg" alt="Maple `Keyless` Base b Encryption Scheme" align="left"/>In this submission it will be shown that the convert/base built-in function can be used to create many new tools which can encrypt or decrypt any file selected. Such a tool, named Maple "keyless` base b encryption scheme, allows to determine the admissible number of elements of the set of ASCII decimals which will be present in the encrypted file, and to choose all the elements of this set.149026Mon, 01 Jul 2013 04:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyC64K366 "Keyless" File Encryption
http://www.maplesoft.com/applications/view.aspx?SID=147752&ref=Feed
<p>This maplet application fulfilling the role of the secret key uses base 64 encoding scheme non-linear transformations for encrypting or decrypting e-mailed files. The encrypted files with extension ".e64" contain only 64 characters belonging to the set of base 64 encoding scheme alphabet and 23 characters "()<>[]{}|-*^_!?@#$%&,:;". The application uses original encryption tool named C64K366. The number following the letter "C" means that any encrypted file contains only 64 characters with ASCII decimals belonging to the set {33, 35 .. 38, 40 .. 45, 47 .. 60, 62 .. 91, 93 .. 95, 97 .. 125}. K366 means that the secret key length equals to 366 bits. For proper functioning of the application, the c64k366.maplet must be saved in a location with no spaces in the path name. </p><img src="/applications/images/app_image_blank_lg.jpg" alt="C64K366 "Keyless" File Encryption" align="left"/><p>This maplet application fulfilling the role of the secret key uses base 64 encoding scheme non-linear transformations for encrypting or decrypting e-mailed files. The encrypted files with extension ".e64" contain only 64 characters belonging to the set of base 64 encoding scheme alphabet and 23 characters "()<>[]{}|-*^_!?@#$%&,:;". The application uses original encryption tool named C64K366. The number following the letter "C" means that any encrypted file contains only 64 characters with ASCII decimals belonging to the set {33, 35 .. 38, 40 .. 45, 47 .. 60, 62 .. 91, 93 .. 95, 97 .. 125}. K366 means that the secret key length equals to 366 bits. For proper functioning of the application, the c64k366.maplet must be saved in a location with no spaces in the path name. </p>147752Mon, 27 May 2013 04:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyThe SHA-3 family of hash functions and their use for message authentication
http://www.maplesoft.com/applications/view.aspx?SID=146570&ref=Feed
<p>Implementation of the cryptographic hash functions based on the Keccak sponge function (designed by G. Bertoni, J. Daemen, M. Peeters and G. Van Assche) which was declared on October 2, 2012 the winner of the NIST Hash Function Competition. These hash functions are going to be integrated in the upcoming SHA-3 standard, which is currently being developed by NIST. The Message Authentication Code HMAC-SHA-3, based on these functions, is also implemented.</p><img src="/view.aspx?si=146570/SHA3family_thumb.png" alt="The SHA-3 family of hash functions and their use for message authentication" align="left"/><p>Implementation of the cryptographic hash functions based on the Keccak sponge function (designed by G. Bertoni, J. Daemen, M. Peeters and G. Van Assche) which was declared on October 2, 2012 the winner of the NIST Hash Function Competition. These hash functions are going to be integrated in the upcoming SHA-3 standard, which is currently being developed by NIST. The Message Authentication Code HMAC-SHA-3, based on these functions, is also implemented.</p>146570Wed, 01 May 2013 04:00:00 ZJosé Luis Gómez PardoJosé Luis Gómez PardoThe Advanced Encryption Standard and its modes of operation
http://www.maplesoft.com/applications/view.aspx?SID=6618&ref=Feed
<p>This is an update, labeled version 1.1, to the existing application The Advanced Encryption Standard and its modes of operation.</p>
<p>Version 1.1: Key generation function and related functions updated to facilitate the use of externally generated seeds. Some minor changes to presentation.</p>
<p>Version 1.0: Implementation of encryption and authentication schemes that use the Advanced Encryption Standard (AES) as their underlying block cipher. These schemes are constructed by using all the modes of operation for block ciphers so far approved by NIST (the US National Institute of Standards of Technology), namely, the five confidentiality modes: ECB, CBC, CFB, OFB and CTR, the authentication mode CMAC, and the "authenticated encryption" modes CCM and GCM/GMAC. The implementation is able to encrypt/decrypt and/or authenticate messages in several formats, including binary files, and we use it to explore the basic properties of these schemes. The implementation contains also detailed explanations of all the procedures used, including the lower level ones, and discusses both the programming and the cryptographic aspects involved.</p><img src="/view.aspx?si=6618/AES_1608.gif" alt="The Advanced Encryption Standard and its modes of operation" align="left"/><p>This is an update, labeled version 1.1, to the existing application The Advanced Encryption Standard and its modes of operation.</p>
<p>Version 1.1: Key generation function and related functions updated to facilitate the use of externally generated seeds. Some minor changes to presentation.</p>
<p>Version 1.0: Implementation of encryption and authentication schemes that use the Advanced Encryption Standard (AES) as their underlying block cipher. These schemes are constructed by using all the modes of operation for block ciphers so far approved by NIST (the US National Institute of Standards of Technology), namely, the five confidentiality modes: ECB, CBC, CFB, OFB and CTR, the authentication mode CMAC, and the "authenticated encryption" modes CCM and GCM/GMAC. The implementation is able to encrypt/decrypt and/or authenticate messages in several formats, including binary files, and we use it to explore the basic properties of these schemes. The implementation contains also detailed explanations of all the procedures used, including the lower level ones, and discusses both the programming and the cryptographic aspects involved.</p>6618Mon, 20 Jun 2011 04:00:00 ZJosé Luis Gómez PardoJosé Luis Gómez PardoMaplets for Using and Exploring a Symmetric-Key Block Cipher Generating Cryptograms with Defined Set of Characters
http://www.maplesoft.com/applications/view.aspx?SID=34939&ref=Feed
<p>Maplets for Using and Exploring a Symmetric-Key Block Cipher Generating Cryptograms with Defined Set of Characters.</p>
<p>Unpack the file foac.zip, open the file foap.mw and explore the cipher.</p><img src="/view.aspx?si=34939/0\foac/ptf/m.jpg" alt="Maplets for Using and Exploring a Symmetric-Key Block Cipher Generating Cryptograms with Defined Set of Characters" align="left"/><p>Maplets for Using and Exploring a Symmetric-Key Block Cipher Generating Cryptograms with Defined Set of Characters.</p>
<p>Unpack the file foac.zip, open the file foap.mw and explore the cipher.</p>34939Wed, 09 Dec 2009 05:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyMLF/MIFF Public-Key Steganocryptography Destined for E-mail Protection
http://www.maplesoft.com/applications/view.aspx?SID=7251&ref=Feed
An easy to use maplet application based on MLF/MIFF public-key steganocryptography for very safe e-mail cryptographic protection. The abbreviation MLF/MIFF stands for Maple language file/Maple internal format file because the delivered software converts any plaintext file of any format containing text, image, voice or music into the cryptogram in the form of a Maple language file or Maple internal format file and restores the plaintext message from the cryptogram. The cryptogram is generated using the generalized ElGamal system.
Instructions: Unpack the file gelg.zip, open the worksheet gelgexpl.mw, and follow the instructons contained inside.<img src="/view.aspx?si=7251//applications/images/app_image_blank_lg.jpg" alt="MLF/MIFF Public-Key Steganocryptography Destined for E-mail Protection" align="left"/>An easy to use maplet application based on MLF/MIFF public-key steganocryptography for very safe e-mail cryptographic protection. The abbreviation MLF/MIFF stands for Maple language file/Maple internal format file because the delivered software converts any plaintext file of any format containing text, image, voice or music into the cryptogram in the form of a Maple language file or Maple internal format file and restores the plaintext message from the cryptogram. The cryptogram is generated using the generalized ElGamal system.
Instructions: Unpack the file gelg.zip, open the worksheet gelgexpl.mw, and follow the instructons contained inside.7251Wed, 18 Feb 2009 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyCryptographic Protection of Definite PC Directory Using the AES Algorithm
http://www.maplesoft.com/applications/view.aspx?SID=7086&ref=Feed
It has been shown how to use the AES algorithm for cryptographic protection of files stored in the definite directory of the PC hard disk by means of the user-friendly maplets.<img src="/view.aspx?si=7086/1.jpg" alt="Cryptographic Protection of Definite PC Directory Using the AES Algorithm" align="left"/>It has been shown how to use the AES algorithm for cryptographic protection of files stored in the definite directory of the PC hard disk by means of the user-friendly maplets.7086Tue, 06 Jan 2009 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyGrayscale Image Steganography
http://www.maplesoft.com/applications/view.aspx?SID=6878&ref=Feed
A new way of steganography consisting in converting an arbitrary message file of any format into a steganogram having the form of grayscale image file (tif or bmp) has been presented. It also has been shown how to protect disk files against unauthorized access using the delivered software.<img src="/view.aspx?si=6878/gsish_1.gif" alt="Grayscale Image Steganography" align="left"/>A new way of steganography consisting in converting an arbitrary message file of any format into a steganogram having the form of grayscale image file (tif or bmp) has been presented. It also has been shown how to protect disk files against unauthorized access using the delivered software.6878Tue, 11 Nov 2008 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyDifferential Equations
http://www.maplesoft.com/applications/view.aspx?SID=6536&ref=Feed
This set of class notes were developed over many years of teaching Differential Equations to the Engineering students (and some others) at NSAC. It consists of a table of contents linked to 8 other worksheets (cpt 1 notes - cpt 8 notes). The topics are those found in a standard Introduction to Differential Equations course starting with an Introduction through to Fourier Series Methods. These notes are also accompanied by a solutions manual for the exercises found in the various sections of the notes.
I hope they will be as useful for you and your students as they have been for mine.<img src="/view.aspx?si=6536/Untitled-1.jpg" alt="Differential Equations" align="left"/>This set of class notes were developed over many years of teaching Differential Equations to the Engineering students (and some others) at NSAC. It consists of a table of contents linked to 8 other worksheets (cpt 1 notes - cpt 8 notes). The topics are those found in a standard Introduction to Differential Equations course starting with an Introduction through to Fourier Series Methods. These notes are also accompanied by a solutions manual for the exercises found in the various sections of the notes.
I hope they will be as useful for you and your students as they have been for mine.6536Thu, 07 Aug 2008 00:00:00 ZProf. Carl MadiganProf. Carl MadiganA Symmetric-Key Block Cipher Generating Cryptograms Containing Characters Belonging to the Definite Set
http://www.maplesoft.com/applications/view.aspx?SID=5646&ref=Feed
A new conception of strong symmetric-key block cipher of byte-oriented architecture has been
presented. The application is intended as an initial step on the way at the end of which cryptography and steganography converge. The issue is that the encryption procedure should be able to turn a plaintext file into a cryptogram in the form of a file containing quite reasonable message but unrelated to the plaintext file. For example, we could want to convert a phone call
representing the plaintext file into the cryptogram file being the photo of a spacecraft. After such action the cryptogram is quite different from classic cryptograms looking usually as outputs
of random ASCII characters generator. The method of encryption presented here produces cryptogram files comprised of characters which belong to the set determined by the cryptographic key, using the operations of conversion between bases and substitution. In general, the cipher is redundant, i.e. the size of the cryptogram file is usually greater than that of the plaintext file.<img src="/view.aspx?si=5646/m.jpg" alt="A Symmetric-Key Block Cipher Generating Cryptograms Containing Characters Belonging to the Definite Set" align="left"/>A new conception of strong symmetric-key block cipher of byte-oriented architecture has been
presented. The application is intended as an initial step on the way at the end of which cryptography and steganography converge. The issue is that the encryption procedure should be able to turn a plaintext file into a cryptogram in the form of a file containing quite reasonable message but unrelated to the plaintext file. For example, we could want to convert a phone call
representing the plaintext file into the cryptogram file being the photo of a spacecraft. After such action the cryptogram is quite different from classic cryptograms looking usually as outputs
of random ASCII characters generator. The method of encryption presented here produces cryptogram files comprised of characters which belong to the set determined by the cryptographic key, using the operations of conversion between bases and substitution. In general, the cipher is redundant, i.e. the size of the cryptogram file is usually greater than that of the plaintext file.5646Thu, 07 Feb 2008 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyProtection of Disk Files Against Unauthorized Access
http://www.maplesoft.com/applications/view.aspx?SID=5085&ref=Feed
One of many possible user-friendly implementations of byte-oriented and practically unbreakable quasigroup-based stream-cipher has been presented. Using this worksheet the reader can also verify statistical properties of plain texts and cryptograms.
Unpack the zip file on disk C, open the worksheet C:/cryptor/ecf.mw, read it and execute.<img src="/view.aspx?si=5085//applications/images/app_image_blank_lg.jpg" alt="Protection of Disk Files Against Unauthorized Access" align="left"/>One of many possible user-friendly implementations of byte-oriented and practically unbreakable quasigroup-based stream-cipher has been presented. Using this worksheet the reader can also verify statistical properties of plain texts and cryptograms.
Unpack the zip file on disk C, open the worksheet C:/cryptor/ecf.mw, read it and execute.5085Wed, 11 Jul 2007 00:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyGenAES Package
http://www.maplesoft.com/applications/view.aspx?SID=4882&ref=Feed
The GenAES package is a collection of routines for exploring AES, for computer-aided design related to AES strong symmetric-key block ciphers which allow to encrypt 128-bit block of data with the key of length from 128 to 3736 bits, and for encrypting files by means of the conventional and modified form of this algorithm, using Maple. The package is a noteworthy tool suitable for those engineers, teachers and students who deal with algebraic methods of strong symmetric-key block ciphers design.<img src="/applications/images/app_image_blank_lg.jpg" alt="GenAES Package" align="left"/>The GenAES package is a collection of routines for exploring AES, for computer-aided design related to AES strong symmetric-key block ciphers which allow to encrypt 128-bit block of data with the key of length from 128 to 3736 bits, and for encrypting files by means of the conventional and modified form of this algorithm, using Maple. The package is a noteworthy tool suitable for those engineers, teachers and students who deal with algebraic methods of strong symmetric-key block ciphers design.4882Sun, 11 Mar 2007 05:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyUsing the GenDES Package to Experiment With DES-768 Encryption
http://www.maplesoft.com/applications/view.aspx?SID=4875&ref=Feed
It has been shown in the worksheet how to apply DES using the GenDES package for encryption 64-bit blocks of data with the secret key length equal to maximum 768 bits<img src="/view.aspx?si=4875//applications/images/app_image_blank_lg.jpg" alt="Using the GenDES Package to Experiment With DES-768 Encryption" align="left"/>It has been shown in the worksheet how to apply DES using the GenDES package for encryption 64-bit blocks of data with the secret key length equal to maximum 768 bits4875Tue, 27 Feb 2007 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyInvestigating the DES Properties Using the GenDES Package
http://www.maplesoft.com/applications/view.aspx?SID=1764&ref=Feed
It has been shown in the worksheet GenDES1.mw how to begin the exploration of DES using the Maple GenDES package.
<P>
The GenDES package is a collection of routines for exploring DES, for computer-aided design related to DES secure symmetric-key block ciphers which allow to encrypt 64-bit block of data with the key of maximal length from 768 to 2359 bits, and for encrypting files by means of the old and generalized form of this algorithm, using Maple. The package is a noteworthy tool suitable for engineers, teachers and students who deal with symmetric-key iterative block ciphers design.<img src="/view.aspx?si=1764/gendes.gif" alt="Investigating the DES Properties Using the GenDES Package" align="left"/>It has been shown in the worksheet GenDES1.mw how to begin the exploration of DES using the Maple GenDES package.
<P>
The GenDES package is a collection of routines for exploring DES, for computer-aided design related to DES secure symmetric-key block ciphers which allow to encrypt 64-bit block of data with the key of maximal length from 768 to 2359 bits, and for encrypting files by means of the old and generalized form of this algorithm, using Maple. The package is a noteworthy tool suitable for engineers, teachers and students who deal with symmetric-key iterative block ciphers design.1764Wed, 19 Jul 2006 04:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyExploring the Modified IDEA Using the topicIDEA Package
http://www.maplesoft.com/applications/view.aspx?SID=1714&ref=Feed
Normally, the IDEA operates on 64-bit blocks using a 128-bit user-selected secret key. Out of this 128-bit key fifty two key subblocks of 16-bit are generated and used in the encryption process. The 52 16-bit key subblocks needed in decryption are computed from the encryption key subblocks. In the modified mode of encryption/decryption by means of the IDEA algorithm the user does not select the 128-bit key but chooses directly the 52 16-bit key subblocks for encryption and employs them as a secret key. In this way IDEA can protect a 64-bit block of data using 832-bit key. By making this new secret key partly public we can encipher/decipher by means of the IDEA using a key of an arbitrary length, but no longer than 832 bits.<img src="/view.aspx?si=1714//applications/images/app_image_blank_lg.jpg" alt="Exploring the Modified IDEA Using the topicIDEA Package" align="left"/>Normally, the IDEA operates on 64-bit blocks using a 128-bit user-selected secret key. Out of this 128-bit key fifty two key subblocks of 16-bit are generated and used in the encryption process. The 52 16-bit key subblocks needed in decryption are computed from the encryption key subblocks. In the modified mode of encryption/decryption by means of the IDEA algorithm the user does not select the 128-bit key but chooses directly the 52 16-bit key subblocks for encryption and employs them as a secret key. In this way IDEA can protect a 64-bit block of data using 832-bit key. By making this new secret key partly public we can encipher/decipher by means of the IDEA using a key of an arbitrary length, but no longer than 832 bits.1714Mon, 27 Feb 2006 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnytopicIDEA Package
http://www.maplesoft.com/applications/view.aspx?SID=1706&ref=Feed
The topicIDEA package is a collection of routines with examples for the exploration of the IDEA algorithm and experimenting with encrypting/decrypting 64-bit block of data by means this algorithm, using Maple.<img src="/view.aspx?si=1706/idea.JPG" alt="topicIDEA Package" align="left"/>The topicIDEA package is a collection of routines with examples for the exploration of the IDEA algorithm and experimenting with encrypting/decrypting 64-bit block of data by means this algorithm, using Maple.1706Mon, 23 Jan 2006 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyThe MLA Steganography
http://www.maplesoft.com/applications/view.aspx?SID=1707&ref=Feed
Steganography means the art and science of hiding information by embedding covert messages within other, ostensibly innocent messages. In most cases steganography works by replacing bits of useless or unused data in habitual computer files with bits of different, invisible secret information. The MLA steganography is quite different and consists in converting any number of arbitrary format files into a Maple .mla file. It is evident that an average Maple user cannot be able to recover the original files hidden in the Maple Library Archive file. Therefore, the presented method can be useful, inter alia, in protecting files against unauthorized copying.<img src="/view.aspx?si=1707//applications/images/app_image_blank_lg.jpg" alt="The MLA Steganography" align="left"/>Steganography means the art and science of hiding information by embedding covert messages within other, ostensibly innocent messages. In most cases steganography works by replacing bits of useless or unused data in habitual computer files with bits of different, invisible secret information. The MLA steganography is quite different and consists in converting any number of arbitrary format files into a Maple .mla file. It is evident that an average Maple user cannot be able to recover the original files hidden in the Maple Library Archive file. Therefore, the presented method can be useful, inter alia, in protecting files against unauthorized copying.1707Mon, 23 Jan 2006 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyMersenne Primes-Based Symmetric-Key Masquerade Block Cipher
http://www.maplesoft.com/applications/view.aspx?SID=1689&ref=Feed
A strong cryptographic system, consisting of very simple encrypting/decrypting algorithms, has been described. The system presented is a sort of a flexible symetric-key block cipher in which plaintext blocks, ciphertext blocks and keys have a form of files. Flexibility denotes here that the size and the format of a plaintext file and a cryptogram file may be arbitrary. The size of the plaintext and cryptogram file may vary from 2 to 3245619 bytes. The system can have a very huge keyspace (key size from 16 to 25964952 bits, while AES offers maximum 256 bits) and works in a masquerade mode. As regards the masquerade mode of operation, it should be emphasized that in this mode the cipher provides cryptograms entirely statistically independent on plaintexts, and the only method of breaking the cipher is the exhaustive search of the key space.<img src="/view.aspx?si=1689//applications/images/app_image_blank_lg.jpg" alt="Mersenne Primes-Based Symmetric-Key Masquerade Block Cipher" align="left"/>A strong cryptographic system, consisting of very simple encrypting/decrypting algorithms, has been described. The system presented is a sort of a flexible symetric-key block cipher in which plaintext blocks, ciphertext blocks and keys have a form of files. Flexibility denotes here that the size and the format of a plaintext file and a cryptogram file may be arbitrary. The size of the plaintext and cryptogram file may vary from 2 to 3245619 bytes. The system can have a very huge keyspace (key size from 16 to 25964952 bits, while AES offers maximum 256 bits) and works in a masquerade mode. As regards the masquerade mode of operation, it should be emphasized that in this mode the cipher provides cryptograms entirely statistically independent on plaintexts, and the only method of breaking the cipher is the exhaustive search of the key space.1689Mon, 14 Nov 2005 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnySecure Symmetric-Key Block Cipher Based on Generalized Finite Fields
http://www.maplesoft.com/applications/view.aspx?SID=1672&ref=Feed
Taking into account the need for personal communications impervious to eavesdroppers, and commercial communications resistant to industrial espionage, the author shows how to build very strong and flexible, yet easily implemented symmetric-key block cipher, using an algebraic system, which can be a little "defective", and which is named a generalized finite field. The cipher presented works in CBC mode, may practically have any block length, any key length, and can be used for encrypting messages of any kind and of any size.<img src="/view.aspx?si=1672/gffbskbc.JPG" alt="Secure Symmetric-Key Block Cipher Based on Generalized Finite Fields" align="left"/>Taking into account the need for personal communications impervious to eavesdroppers, and commercial communications resistant to industrial espionage, the author shows how to build very strong and flexible, yet easily implemented symmetric-key block cipher, using an algebraic system, which can be a little "defective", and which is named a generalized finite field. The cipher presented works in CBC mode, may practically have any block length, any key length, and can be used for encrypting messages of any kind and of any size.1672Tue, 11 Oct 2005 00:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyFrequency Analysis and the Kama Sutra Substitution Cipher
http://www.maplesoft.com/applications/view.aspx?SID=1661&ref=Feed
In the 4th century BC, the Indian text "Kama Sutra" proposed a method of encrypting text. Each letter of the alphabet was paired with one other letter. A ciphertext was formed by replacing each letter in the plaintext with its paired letter. When this scheme is used in the English language, the number of possible keys is surprisingly high: around 7.9 * 10^12. An exhaustive attack on such a scheme would be unwieldly using a modern computer, and it was certainly infeasible at the time this scheme was suggested.
The art of cryptanalysis (systematic techniques used to break ciphers) traces back to Arab Islamic society, from 750-900 AD. al Kindi proposed the technique of frequency analysis to break substitution ciphers like that proposed in the Kama Sutra text. Frequency analysis recognizes that in long blocks of text, certain letters tend to occur much more frequently than others. When a big enough sample text is used in a particular language, certain patterns occur predictably, for example in English text, the most common letters are E, T and N while Q and Z are used infrequently. Different languages have different typical frequency patterns.
In this worksheet, letters of the English alphabet will be paired at random according to the Kama Sutra scheme. A block of text will be encrypted by swapping letters according to this pairing. The user can refer to the frequency patterns for the English language and the letter frequencies in the ciphertext to try to determine the letter pairings and hence receover the original plaintext. The Maplet uses the user's pairing of letters to guess at the plaintext, and tracks how many guesses have been made.<img src="/view.aspx?si=1661/KamaSutraFrequency2.JPG" alt="Frequency Analysis and the Kama Sutra Substitution Cipher" align="left"/>In the 4th century BC, the Indian text "Kama Sutra" proposed a method of encrypting text. Each letter of the alphabet was paired with one other letter. A ciphertext was formed by replacing each letter in the plaintext with its paired letter. When this scheme is used in the English language, the number of possible keys is surprisingly high: around 7.9 * 10^12. An exhaustive attack on such a scheme would be unwieldly using a modern computer, and it was certainly infeasible at the time this scheme was suggested.
The art of cryptanalysis (systematic techniques used to break ciphers) traces back to Arab Islamic society, from 750-900 AD. al Kindi proposed the technique of frequency analysis to break substitution ciphers like that proposed in the Kama Sutra text. Frequency analysis recognizes that in long blocks of text, certain letters tend to occur much more frequently than others. When a big enough sample text is used in a particular language, certain patterns occur predictably, for example in English text, the most common letters are E, T and N while Q and Z are used infrequently. Different languages have different typical frequency patterns.
In this worksheet, letters of the English alphabet will be paired at random according to the Kama Sutra scheme. A block of text will be encrypted by swapping letters according to this pairing. The user can refer to the frequency patterns for the English language and the letter frequencies in the ciphertext to try to determine the letter pairings and hence receover the original plaintext. The Maplet uses the user's pairing of letters to guess at the plaintext, and tracks how many guesses have been made.1661Tue, 30 Aug 2005 00:00:00 ZJudith KoellerJudith Koeller