Cryptography: New Applications
http://www.maplesoft.com/applications/category.aspx?cid=135
en-us2015 Maplesoft, A Division of Waterloo Maple Inc.Maplesoft Document SystemTue, 26 May 2015 11:52:00 GMTTue, 26 May 2015 11:52:00 GMTNew applications in the Cryptography categoryhttp://www.mapleprimes.com/images/mapleapps.gifCryptography: New Applications
http://www.maplesoft.com/applications/category.aspx?cid=135
ElGamal E-mail Encryption Scheme
http://www.maplesoft.com/applications/view.aspx?SID=153538&ref=Feed
<p>The submission shows how to implement the user-friendly, but mathematically sophisticated strong e-mail encryption scheme using the ElGamal algorithm working in the multiplicative group of GF(p^m) (http://www.maplesoft.com/applications/view.aspx?SID=4403, J. L. G. Pardo - Introduction to Cryptography with Maple). On unpacking the file `elgmail.zip` the user will see three public key files: `ElGpub_Eve_Flower.m`, `ElGpub_Jack_Herod.m`, `ElGpub_Michele_Lazy.m` and three application worksheets: `ElGedm_Flower.mw`, `ElGedm_Herod.mw`, `ElGedm_Lazy.mw` in which the proper private keys are embedded. Each of the three users can encrypt an e-mail letter and can send the encrypted message to the required addressee, knowing its public key. Evidently, any user can also decrypt the proper encrypted message, addressed to him. The way of generating the public and private keys demonstrates the worksheet ElGkg.mw. The data contained in the names of the computed keys using the worksheet ElGkg.mw is evident. In the presented example the e-mail message should contain no more than 782 printable characters with byte values less than 127. The scheme can be accepted for any e-mail system: the public keys and encrypted messages are Maple `*.m` format files containing characters with 91 byte values from the set {10, 33 .. 122}. The user can also observe the time needed for encryption, decryption and the computation of keys, and the encryption scheme redundancy. An example test message and its cryptogram is also presented and the user can check for which the encrypted test message ought to be sent.</p><img src="/view.aspx?si=153538/image.PNG" alt="ElGamal E-mail Encryption Scheme" align="left"/><p>The submission shows how to implement the user-friendly, but mathematically sophisticated strong e-mail encryption scheme using the ElGamal algorithm working in the multiplicative group of GF(p^m) (http://www.maplesoft.com/applications/view.aspx?SID=4403, J. L. G. Pardo - Introduction to Cryptography with Maple). On unpacking the file `elgmail.zip` the user will see three public key files: `ElGpub_Eve_Flower.m`, `ElGpub_Jack_Herod.m`, `ElGpub_Michele_Lazy.m` and three application worksheets: `ElGedm_Flower.mw`, `ElGedm_Herod.mw`, `ElGedm_Lazy.mw` in which the proper private keys are embedded. Each of the three users can encrypt an e-mail letter and can send the encrypted message to the required addressee, knowing its public key. Evidently, any user can also decrypt the proper encrypted message, addressed to him. The way of generating the public and private keys demonstrates the worksheet ElGkg.mw. The data contained in the names of the computed keys using the worksheet ElGkg.mw is evident. In the presented example the e-mail message should contain no more than 782 printable characters with byte values less than 127. The scheme can be accepted for any e-mail system: the public keys and encrypted messages are Maple `*.m` format files containing characters with 91 byte values from the set {10, 33 .. 122}. The user can also observe the time needed for encryption, decryption and the computation of keys, and the encryption scheme redundancy. An example test message and its cryptogram is also presented and the user can check for which the encrypted test message ought to be sent.</p>153538Wed, 02 Apr 2014 04:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyGeneralized byte-oriented fast stream cipher that is resistant to reverse engineering
http://www.maplesoft.com/applications/view.aspx?SID=153499&ref=Feed
<p>A new numerous family of strong, to reverse engineering resistant, and fast byte-oriented stream-ciphers has been presented. One ought to unpack the file gbosc.zip, open the worksheet gbosc.mw in the Maple session, read it and test the application described.</p><img src="/applications/images/app_image_blank_lg.jpg" alt="Generalized byte-oriented fast stream cipher that is resistant to reverse engineering" align="left"/><p>A new numerous family of strong, to reverse engineering resistant, and fast byte-oriented stream-ciphers has been presented. One ought to unpack the file gbosc.zip, open the worksheet gbosc.mw in the Maple session, read it and test the application described.</p>153499Tue, 28 Jan 2014 05:00:00 ZCzeslaw KoscielnyCzeslaw KoscielnyCryptographic directory protection using the byte-oriented stream-cipher of type A256K1024
http://www.maplesoft.com/applications/view.aspx?SID=153483&ref=Feed
<p>This one-worksheet user-friendly application allows to encrypt/decrypt selected by user directory, containing confidential files, by means of practically unbreakable non-redundant byte-oriented cipher of type <strong>A256K1024.</strong> The type cipher name means that the encryption process involves<strong> addition</strong> operation in <strong>GF(256)</strong> and the secret key of length <strong>1024</strong> bytes (8192 bits), which in the application is embedded. The user can replace the application key (the list <strong>K</strong> of 1024 integers in the range 0..255) by his one. </p><img src="/applications/images/app_image_blank_lg.jpg" alt="Cryptographic directory protection using the byte-oriented stream-cipher of type A256K1024" align="left"/><p>This one-worksheet user-friendly application allows to encrypt/decrypt selected by user directory, containing confidential files, by means of practically unbreakable non-redundant byte-oriented cipher of type <strong>A256K1024.</strong> The type cipher name means that the encryption process involves<strong> addition</strong> operation in <strong>GF(256)</strong> and the secret key of length <strong>1024</strong> bytes (8192 bits), which in the application is embedded. The user can replace the application key (the list <strong>K</strong> of 1024 integers in the range 0..255) by his one. </p>153483Mon, 23 Dec 2013 05:00:00 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 Pardochiffrer avec le Code de César en utilisant une clé-phrase
http://www.maplesoft.com/applications/view.aspx?SID=142952&ref=Feed
<p>Cette Maplet utilise une version améliorée du Code de César utilisant une clé-phrase.<br />explications:<br />on prend par exemple avec la clé : "cle"<br />"message codé"</p>
<p> clecleclecle</p>
<p>le m va etre codé avec mon alphabet commençant par c:le i ème caractère de abcdef...... devient le i ème caractère de cdefgh.....<br />le e va etre codé avec mon alphabet commençant par l.</p>
<p>etc...</p>
<p>NB: La clé et le message doivent etre de type "phrase" (string)</p><img src="/view.aspx?si=142952/CaptCesar.JPG" alt="chiffrer avec le Code de César en utilisant une clé-phrase" align="left"/><p>Cette Maplet utilise une version améliorée du Code de César utilisant une clé-phrase.<br />explications:<br />on prend par exemple avec la clé : "cle"<br />"message codé"</p>
<p> clecleclecle</p>
<p>le m va etre codé avec mon alphabet commençant par c:le i ème caractère de abcdef...... devient le i ème caractère de cdefgh.....<br />le e va etre codé avec mon alphabet commençant par l.</p>
<p>etc...</p>
<p>NB: La clé et le message doivent etre de type "phrase" (string)</p>142952Fri, 01 Feb 2013 05:00:00 Zxavier cormierxavier cormierThe 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 PardoRSA with maple
http://www.maplesoft.com/applications/view.aspx?SID=100620&ref=Feed
<h3>The purpose of this<strong> worksheet is to show how can maple be applied to ease the cryptography of messages</strong></h3><img src="/view.aspx?si=100620/maple_icon.jpg" alt="RSA with maple" align="left"/><h3>The purpose of this<strong> worksheet is to show how can maple be applied to ease the cryptography of messages</strong></h3>100620Tue, 04 Jan 2011 05:00:00 ZAli Abu OamAli Abu OamUser Friendly Maple Tools for Preliminary Cryptanalysis
http://www.maplesoft.com/applications/view.aspx?SID=98016&ref=Feed
<p>In this application the easy to use tool has been presented. The user can generate histograms, visualizing the main statistical properties of a selected disk file, by means of the mouse only.</p><img src="/view.aspx?si=98016/maple_icon.jpg" alt="User Friendly Maple Tools for Preliminary Cryptanalysis" align="left"/><p>In this application the easy to use tool has been presented. The user can generate histograms, visualizing the main statistical properties of a selected disk file, by means of the mouse only.</p>98016Thu, 21 Oct 2010 04:00:00 ZProf. Czeslaw KoscielnyProf. Czeslaw KoscielnyMaplets 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 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 Koscielny