Math
Math 115F: Cryptography, Fall 2012
Paper #2 Expository Paper
OVERVIEW
In this paper, youll describe the origin, use,
influence, and mechanics of a code or cipher of
your choice. There are many codes and ciphers
we wont have time to explore in detail
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Cipher
DJQCT JKNQC TNJON DQDPC DPHTP QCTST HQDSQ NDOTP
GJKWJ RPQCT LDSQP SKTXD PQTEA KNSTJ QUNDT PRHKJ
BPDET HDQTN RQTSU HQUNT PPUSC RPQCT NKIRJ PQCTD
NDPCR JEQCT RJBHK PRXKJ PQCTY WTNTQ CTKEE PKSD
Math
Math 115F: Cryptography, Fall 2012
Paper #1 Reaction Paper
For this paper assignment, Im asking you to read and respond to one of the articles listed
below, each dealing with cryptography and its role in society. Youll need to summarize the
thesis an
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Cipher
YMJDY MTZLM YNYYT GJZSG WJFPF GQJFS ISTYB NYMTZ
YLTTI WJFXT SJSNL RFXHT RUQJC NYDBF XGJBN QIJWN
SLYDU NSLNS FQJYY JWTKU QFNSL JWRFS NSYTY MJRFH
MNSJX JSYJQ JHYWN HFQNR UZQXJ XYMWT ZLMFX JWNJ
Solutions to Practice Problems
1.
a.
b.
c.
d.
, -43, -17, 9, 35, 61,
, -22, -18, -14, -10, -6,
, 5, 13, 21, 29, 37,
, 1, 6, 11, 16, 21,
a.
b.
c.
d.
2
0
4
14
2.
3.
a. 312
b. 235711
c. 7319
4.
a.
b.
c.
d.
Not relatively prime
Relatively prime
Relatively
Math115F:Cryptography,Fall2012
Paper#3BigQuestionsPaper
OVERVIEW
For your final assignment, youll be asked to
focus on important questions about the
ways in which cryptography has affected
history, culture, and technology. Youll pose
a significant questio
Problem Set 4
1. Milk Chocolate (aka plain) M&Ms come in six different colors. According to the
manufacturer, 24% of these M&Ms are blue, 14% are brown, 16% are green, 20% are
orange, 13% are red, and 14% are yellow. Suppose you open up a pack of M&Ms and
Problem Set 3
1. The following cipher alphabet was constructed using a keyword columnar transposition
scheme. What was the keyword used?
B D S L F T A G U C I V K J W H N X M O Y E P Z R Q
2. Decipher the following using frequency analysis. Heres a freque
Problem Set 5, Question 4
Question 4 on Problem Set 5 asks for a proof of the second of three conditions that the RSA encryption
scheme must meet to be considered secure and reliable.
Condition 2. The value of x calculated in Step 9 of the RSA algorithm s
Problem Set 2
1. The 30-letter Coptic alphabet is a variant of the Greek alphabet developed when Greece
conquered Egypt in the 3rd century BC1. It consists of all 24 letters of the Greek alphabet, as
well as six addition letters representing sounds not us
Problem Set 5
Part One
1. The key for an ADFGVX cipher consists of some arrangement of the 26 letters of the alphabet
as well as the digits 0 through 9 in a six-by-six grid, plus a keyword used to determine how
certain columns of ciphertext are rearranged
Math 115F Math Exam Study Guide
This weeks math exam will cover the mathematical concepts and techniques weve explored this
semester. The exam will not involve any codebreaking, although some questions on the exam may draw
on cryptography for context. You
Problem Set 1
1. Decipher the following message. You should assume it was enciphered using a
monoalphabetic substitution cipher.
EN VCOCGHCP CEQXDCCN DXEPDM-NENC, BUC EWWKCV A OXAZZCNQC DU DXC PCAVCPW UJ
DXC BXEZAVCZBXEA BABCP AZCFANVCP'W YCCSZM DXAD XC O