<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1405-5546</journal-id>
<journal-title><![CDATA[Computación y Sistemas]]></journal-title>
<abbrev-journal-title><![CDATA[Comp. y Sist.]]></abbrev-journal-title>
<issn>1405-5546</issn>
<publisher>
<publisher-name><![CDATA[Instituto Politécnico Nacional, Centro de Investigación en Computación]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1405-55462012000200010</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Una evidencia robusta de que el algoritmo DES fortalecido con una permutación inicial variable es eficiente]]></article-title>
<article-title xml:lang="en"><![CDATA[A Robust Evidence of the DES Algorithm Strengthened by a Variable Initial Permutation being Efficient]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Flores Carapia]]></surname>
<given-names><![CDATA[Rolando]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Silva García]]></surname>
<given-names><![CDATA[Víctor Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Yáñez Márquez]]></surname>
<given-names><![CDATA[Cornelio]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Camacho Nieto]]></surname>
<given-names><![CDATA[Oscar]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Politécnico Nacional Centro de Innovación y Desarrollo Tecnológico en Cómputo ]]></institution>
<addr-line><![CDATA[México ]]></addr-line>
</aff>
<aff id="A02">
<institution><![CDATA[,Instituto Politécnico Nacional Centro de Investigación en Computación ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2012</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2012</year>
</pub-date>
<volume>16</volume>
<numero>2</numero>
<fpage>249</fpage>
<lpage>254</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1405-55462012000200010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1405-55462012000200010&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1405-55462012000200010&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Utilizando el Teorema JV se puede asociar un numero de tamaño 1089 a una permutación de 64 posiciones en 63 pasos, este resultado se aplicó para reforzar DES mediante una permutación inicial variable, con lo cual se incrementa la complejidad computacional del algoritmo, ya que cada permutación trabaja como una llave. Sin embargo, aun queda pendiente saber cómo actúan la permutación inicial variable y la llave de 56 bits, con relación a la complejidad computacional del algoritmo. En esta investigación, se dará luz al problema anterior, en el sentido de que se propondrá un esquema de Monte Carlo usando el modelo del "Birthday" para el cálculo de probabilidades.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[By using the JV Theorem, it is possible to associate a number of size 1089 to a 64 position permutation in 63 steps. This result has been applied to strengthening the DES algorithm by using a variable initial permutation, increasing the computational complexity of the algorithm, given that each permutation works as a key. However, it still remains to be seen how the variable initial permutation and the 56 bit key work regarding the computational complexity of the algorithm. In the current work, the former question is addressed by proposing a Monte Carlo scheme using the Birthday model for the probability calculation.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Teorema JV]]></kwd>
<kwd lng="es"><![CDATA[modelo birthday]]></kwd>
<kwd lng="es"><![CDATA[DES]]></kwd>
<kwd lng="es"><![CDATA[modelo de decisión de Monte Carlo]]></kwd>
<kwd lng="es"><![CDATA[permutación variable]]></kwd>
<kwd lng="en"><![CDATA[JV theorem]]></kwd>
<kwd lng="en"><![CDATA[birthday model]]></kwd>
<kwd lng="en"><![CDATA[DES]]></kwd>
<kwd lng="en"><![CDATA[Monte Carlo decision model]]></kwd>
<kwd lng="en"><![CDATA[variable permutation]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Art&iacute;culos</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="4"><b>Una evidencia robusta de que el algoritmo DES fortalecido con una permutaci&oacute;n inicial variable es eficiente</b></font></p>  	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="3"><b>A Robust Evidence of the DES Algorithm Strengthened by a Variable Initial Permutation being Efficient</b></font></p>  	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="2"><b>Rolando Flores Carapia, V&iacute;ctor Manuel Silva Garc&iacute;a, Cornelio Y&aacute;&ntilde;ez M&aacute;rquez y Oscar Camacho Nieto</b></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><i>Centro de Innovaci&oacute;n y Desarrollo Tecnol&oacute;gico en C&oacute;mputo, Instituto Polit&eacute;cnico Nacional, M&eacute;xico</i> <a href="mailto:rfcarapia@yahoo.com">rfcarapia@yahoo.com</a> , <a href="mailto:vsilvag@ipn.mx">vsilvag@ipn.mx</a>, <a href="http://www.cidetec.ipn.mx/" target="_blank">www.cidetec.ipn.mx</a></font></p>  	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2"><i>Centro de Investigaci&oacute;n en Computaci&oacute;n, Instituto Polit&eacute;cnico Nacional, M&eacute;xico</i> <a href="mailto:cyanez@cic.ipn.mx">cyanez@cic.ipn.mx</a>, <a href="mailto:oscarc@cic.ipn.mx">oscarc@cic.ipn.mx</a>, <a href="http://www.cornelio.org.mx/" target="_blank">www.cornelio.org.mx</a> , <a href="http://www.cic.ipn.mx" target="_blank">www.cic.ipn.mx</a></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2">Art&iacute;culo recibido el 15/12/2010.    <br> 	Aceptado el 24/10/2011.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>  	    <p align="justify"><font face="verdana" size="2">Utilizando el Teorema JV se puede asociar un numero de tama&ntilde;o 1089 a una permutaci&oacute;n de 64 posiciones en 63 pasos, este resultado se aplic&oacute; para reforzar DES mediante una permutaci&oacute;n inicial variable, con lo cual se incrementa la complejidad computacional del algoritmo, ya que cada permutaci&oacute;n trabaja como una llave. Sin embargo, aun queda pendiente saber c&oacute;mo act&uacute;an la permutaci&oacute;n inicial variable y la llave de 56 bits, con relaci&oacute;n a la complejidad computacional del algoritmo. En esta investigaci&oacute;n, se dar&aacute; luz al problema anterior, en el sentido de que se propondr&aacute; un esquema de Monte Carlo usando el modelo del "Birthday" para el c&aacute;lculo de probabilidades.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> Teorema JV, modelo <i>birthday</i>, DES, modelo de decisi&oacute;n de Monte Carlo, permutaci&oacute;n variable.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>  	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">By using the JV Theorem, it is possible to associate a number of size 1089 to a 64 position permutation in 63 steps. This result has been applied to strengthening the DES algorithm by using a variable initial permutation, increasing the computational complexity of the algorithm, given that each permutation works as a key. However, it still remains to be seen how the variable initial permutation and the 56 bit key work regarding the computational complexity of the algorithm. In the current work, the former question is addressed by proposing a Monte Carlo scheme using the Birthday model for the probability calculation.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Keywords.</b> JV theorem, birthday model, DES, Monte Carlo decision model, variable permutation.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><a href="/pdf/cys/v16n2/v16n2a10.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Referencias</b></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>1. Bailey, D.H. (2011).</b> <i>A Compendium of BBP&#45;Type Formulas for Mathematical Constants</i>. Retrieved from <a href="http://crd.lbl.gov/~dhbailey/dhbpapers/bbp-formulas.pdf" target="_blank">http://crd.lbl.gov/~dhbailey/dhbpapers/bbp&#45;formulas.pdf</a>.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056078&pid=S1405-5546201200020001000001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>2. Bailey, D.H., Plouffe, S.M., Borwein, P.B., &amp; Borwein, J.M. (1997).</b> The Quest for Pi. <i>The Mathematical Intelligencer</i>, 19(1), 50&#150;56.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056080&pid=S1405-5546201200020001000002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2"><b>3. Biham, E. &amp; Shamir, A. (1993).</b> Differential cryptanalysis of the full 16&#45;round DES. <i>Advances in Cryptology&#45;CRYPTO' 92. Lecture Notes inComputer Science</i>, 740, 487&#150;496.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056082&pid=S1405-5546201200020001000003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>4. Daemen, J. &amp; Rijmen, V. (2001).</b> <i>Advances Encryption Standard (AES),</i> FIPS 197.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056084&pid=S1405-5546201200020001000004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>5.</b> <i>Data Encryption Standard (DES),</i> FIPS PUB 46&#45;2, 1993.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056086&pid=S1405-5546201200020001000005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>6.</b> <i>Data Encryption Standard (DES)</i>, FIPS PUB 46&#45;3, 1999.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056088&pid=S1405-5546201200020001000006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>7. Elgamal, T. (1985).</b> A public key cryptosystem and a signature scheme based on discrete logarithms. <i>IEEE Transactions on Information Theory</i>, 31(4), 469&#150;472.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056090&pid=S1405-5546201200020001000007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2"><b>8. Gentle, J.E. (2003).</b> <i>Random Number Generation and Monte Carlo Methods (2nd ed</i>.). New York: Springer.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056092&pid=S1405-5546201200020001000008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>9. G&oacute;mez, A. (2006).</b> <i>Enciclopedia de la Seguridad Informatica</i>. Alfaomega: Mexico.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056094&pid=S1405-5546201200020001000009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>10. Matsui, M. (1994).</b> Linear Cryptanalysis Method for DES cipher. <i>Advances in Cryptology&#45;EUROCRYPT'93. Lecture Notes in Computer Science</i>, 765, 386&#150;397.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056096&pid=S1405-5546201200020001000010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>11. Rivest, R.L., Shamir, A., &amp; Adleman, L. (1978).</b> A method for obtaining digital signatures and Public&#45;key cryptosystems. <i>Communications of the ACM</i>, 21(2), 120&#150;126.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056098&pid=S1405-5546201200020001000011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>12. Rosen, K.H. (2003).</b> <i>Discrete Mathematics and its Applications (5th ed.)</i>. Boston: McGraw Hill.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056100&pid=S1405-5546201200020001000012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2"><b>13. Silva, V.M., Flores, G.R., L&oacute;pez, I., &amp; Renter&iacute;a, C. (2010).</b> Algorithm for Strengthening Some Cryptographic Systems. <i>Journal of Applied Mathematical Sciences</i>, 4(20), 967&#150;976.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056102&pid=S1405-5546201200020001000013&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>14. Spivak, M. (1997).</b> Calculus: C&aacute;lculo Infinitesimal (2nd ed.). Barcelona: Revert&eacute;    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056104&pid=S1405-5546201200020001000014&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref -->.</font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2"><b>15. Stinson, D.R. (2002).</b> <i>Cryptography: Theory and practice (2nd ed.)</i>. Boca Raton: Chapman &amp; Hall/ CRC.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=2056106&pid=S1405-5546201200020001000015&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bailey]]></surname>
<given-names><![CDATA[D.H.]]></given-names>
</name>
</person-group>
<source><![CDATA[A Compendium of BBP-Type Formulas for Mathematical Constants]]></source>
<year>2011</year>
</nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bailey]]></surname>
<given-names><![CDATA[D.H.]]></given-names>
</name>
<name>
<surname><![CDATA[Plouffe]]></surname>
<given-names><![CDATA[S.M.]]></given-names>
</name>
<name>
<surname><![CDATA[Borwein]]></surname>
<given-names><![CDATA[P.B.]]></given-names>
</name>
<name>
<surname><![CDATA[Borwein]]></surname>
<given-names><![CDATA[J.M.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[The Quest for Pi]]></article-title>
<source><![CDATA[The Mathematical Intelligencer]]></source>
<year>1997</year>
<volume>19</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>50-56</page-range></nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Biham]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Shamir]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Differential cryptanalysis of the full 16-round DES]]></article-title>
<source><![CDATA[Advances in Cryptology-CRYPTO' 92. Lecture Notes inComputer Science]]></source>
<year>1993</year>
<volume>740</volume>
<page-range>487-496</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Daemen]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Rijmen]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
</person-group>
<source><![CDATA[Advances Encryption Standard]]></source>
<year>2001</year>
<page-range>197</page-range><publisher-name><![CDATA[FIPS]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="">
<collab>Data Encryption Standard</collab>
<source><![CDATA[FIPS PUB]]></source>
<year>1993</year>
<page-range>46-2</page-range></nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="">
<collab>Data Encryption Standard</collab>
<source><![CDATA[FIPS PUB]]></source>
<year>1999</year>
<page-range>46-3</page-range></nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Elgamal]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[A public key cryptosystem and a signature scheme based on discrete logarithms]]></article-title>
<source><![CDATA[IEEE Transactions on Information Theory]]></source>
<year>1985</year>
<volume>31</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>469-472</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>8</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gentle]]></surname>
<given-names><![CDATA[J.E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Random Number Generation and Monte Carlo Methods (2nd ed.)]]></source>
<year>2003</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B9">
<label>9</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gómez]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Enciclopedia de la Seguridad Informatica]]></source>
<year>2006</year>
<publisher-loc><![CDATA[Mexico ]]></publisher-loc>
<publisher-name><![CDATA[Alfaomega]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<label>10</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Matsui]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Linear Cryptanalysis Method for DES cipher]]></article-title>
<source><![CDATA[Advances in Cryptology-EUROCRYPT'93. Lecture Notes in Computer Science]]></source>
<year>1994</year>
<volume>765</volume>
<page-range>386-397</page-range></nlm-citation>
</ref>
<ref id="B11">
<label>11</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rivest]]></surname>
<given-names><![CDATA[R.L.]]></given-names>
</name>
<name>
<surname><![CDATA[Shamir]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Adleman]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[A method for obtaining digital signatures and Public-key cryptosystems]]></article-title>
<source><![CDATA[Communications of the ACM]]></source>
<year>1978</year>
<volume>21</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>120-126</page-range></nlm-citation>
</ref>
<ref id="B12">
<label>12</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rosen]]></surname>
<given-names><![CDATA[K.H.]]></given-names>
</name>
</person-group>
<source><![CDATA[Discrete Mathematics and its Applications (5th ed.)]]></source>
<year>2003</year>
<publisher-loc><![CDATA[Boston ]]></publisher-loc>
<publisher-name><![CDATA[McGraw Hill]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<label>13</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Silva]]></surname>
<given-names><![CDATA[V.M.]]></given-names>
</name>
<name>
<surname><![CDATA[Flores]]></surname>
<given-names><![CDATA[G.R.]]></given-names>
</name>
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Rentería]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Algorithm for Strengthening Some Cryptographic Systems]]></article-title>
<source><![CDATA[Journal of Applied Mathematical Sciences]]></source>
<year>2010</year>
<volume>4</volume>
<numero>20</numero>
<issue>20</issue>
<page-range>967-976</page-range></nlm-citation>
</ref>
<ref id="B14">
<label>14</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Spivak]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Calculus: Cálculo Infinitesimal]]></source>
<year>1997</year>
<edition>2nd</edition>
<publisher-loc><![CDATA[Barcelona ]]></publisher-loc>
<publisher-name><![CDATA[Reverté]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B15">
<label>15</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stinson]]></surname>
<given-names><![CDATA[D.R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Cryptography: Theory and practice]]></source>
<year>2002</year>
<edition>2nd</edition>
<publisher-loc><![CDATA[Boca Raton ]]></publisher-loc>
<publisher-name><![CDATA[Chapman & HallCRC]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
