# ACCESS - Cryptography 2013

## June 24-28, 8:30am-12pm (AM Session)

• Instructor: Fernando Guevara Vasquez (fguevara AT math DOT utah DOT edu), LCB 212, 801-581-7467.
• ACCESS TA: Rachel Petragallo (rachel DOT marie AT live DOT com)
• Math TA: Cheryl Zapata (zapata AT math DOT utah DOT edu)
• Where: Please refer to the campus map for the location of buildings. Both JTB (John Talmage Building) and LCB (LeRoy Cowles Building) are on the President's Circle. MAC 1008 is a computer lab in the Marriott Library.
• Monday (JTB 120)
• Tuesday (MAC 1008)
• [8:30-9] History behind Caesar shifts, substitution ciphers and how to defeat them with frequency analysis.
• [9-11] Cracking a substitution cipher via frequency analysis using Maple. (instructions here)
• [11-12] The Euclidean algorithm. Greatest Common Divisor. (notes: Euclid.pdf)
• Assignment for Wed: Exercises 2,4,5 in Euclidean notes.
• Wednesday (JTB 120)
• [8:30-9:30] Modular Powers. (notes: modularpowers.pdf)
• [9:30-11] Theory of public key cryptography (RSA). (notes by Tom Davis. The Code Book, by Simon Singh, also explains RSA in Chapter 6 and Appendix J).
• [11-12] Mathematics round table.
• Thursday (JTB 120)
• Friday (MAC 1008)
• [8:30-12] Public Key Cryptography with Maple. (notes: alicebob.pdf)
• Project: Public Key Cryptography with signature in Maple. Due: Friday July 12 2013.
• Project instructions: project1.pdf.
• Maple file: RSA.mw and illustration RSAverbose.pdf.
• Converting letters into numbers and vice versa with the Davis table can be done here. This will also count the number of characters that you are using in your message.
• And here is the link to verify your numbers. You need to verify your numbers using this link in order for me to publish them below for other groups to use. The verification link will only be active for Friday.
• Public key directory
• Group 1: Anastasia, Erin, Katie
•   N  = 8968464964200403078172078523315732947782991354404876671300551
e  = 6187921242921398781452319111113

• Group 2: Rachel, Maria, Caroline
•   N  = 28272864532705846923024602688511038459707384839327355425300261
e  = 1453768818035425586345626849745

• Group 3: Ashley, Samantha, Amber
•   N  = 58262574511793346706904231186226373910787736653400128532594457
e  = 6665228376119096550705185666807

• Group 4: Katsyarina, Catherine, Alia
•   N  = 51125209179358700687147327769207653294344527033511107541068313
e  = 4544462060873238177881217794505

• Group 5: Brianna, Olimpia, Karlee
•   N  = 21176586241749911912501164545510793312187248487358510567976891
e  = 2710213271797645423839529663483

• Group 6: Nikole, Elizabeth, Yennhi
•   N  = 64438637177454822610867030379986957894905693385406029158293659
e  = 7860368406722160406621622262143

• Group 7: Emma, Shalauna, Haysun
•   N  = 37076200517172054683038900679893221867453852477695727232332659
e  = 3442014381535799923932414648043

This class is based on previous ACCESS classes by Nick Korevaar