6. (a) Encipher the message HAPPY DAYS ARE HERE using the autokey cipher with seed Q. (b) Decipher the message BBOT XWBZ AWUVGK, which was produced by the autokey cipher with seed RX.
6. (a) Encipher the message HAPPY DAYS ARE HERE using the autokey cipher with seed Q. (b) Decipher the message BBOT XWBZ AWUVGK, which was produced by the autokey cipher with seed RX.
Computer Networking: A Top-Down Approach (7th Edition)
7th Edition
ISBN:9780133594140
Author:James Kurose, Keith Ross
Publisher:James Kurose, Keith Ross
Chapter1: Computer Networks And The Internet
Section: Chapter Questions
Problem R1RQ: What is the difference between a host and an end system? List several different types of end...
Related questions
Question
Question 6
![208
ELEMENTARY NUMBER THEORY
4. In a lengthy ciphertext message, sent using a linear cipher C = a P + b (mod 26), the
most frequently occurring letter is Q and the second most frequent is J.
(a) Break the cipher by determining the values of a and b.
[Hint: The most often used letter in English text is E, followed by T.]
(b) Write out the plaintext for the intercepted message WCPQ JZQO MX.
5. (a) Encipher the message HAVE A NICE TRIP using a Vigenère cipher with the keyword
MATH.
(b) The ciphertext BS FMX KFSGR JAPWL is known to have resulted from a Vigenère
cipher whose keyword is YES. Obtain the deciphering congruences and read the
message.
6. (a) Encipher the message HAPPY DAYS ARE HERE using the autokey cipher with
seed Q.
(b) Decipher the message BBOT XWBZ AWUVGK, which was produced by the autokey
cipher with seed RX.
7. (a) Use the Hill cipher
C1 = 5P1 + 2P2 (mod 26)
biopje
C2 = 3P¡ +4 P2 (mod 26)
to encipher the message GIVE THÊM TIME.
(b) The ciphertext ALXWU VADCOJO has been enciphered with the cipher
C1 = 4P1+11P2 (mod 26)
bo
Geft
-130
C2 = 3P1 + 8 P2 (mod 26)
Derive the plaintext.
8. A long string of ciphertext resulting from a Hill cipher
C1 = lc
a P1 + b P2 (mod 26)
our beuog
C2 = cP1+d P2 (mod 26)
coveeled that the most frequently occurring two-letter bl0cks were HO and PP, in that
order.
(a) Find the values of a, b, c, and d.
THint: The most common two0-letter biocks in the English language are TH, followed
(b) What is the plaintext for the intercepted meson](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F66c7b497-dac7-4855-b923-2e60bbc73063%2Fc00b3fc9-42cc-48bc-b477-2564a1a0b69d%2F0njzenl.jpeg&w=3840&q=75)
Transcribed Image Text:208
ELEMENTARY NUMBER THEORY
4. In a lengthy ciphertext message, sent using a linear cipher C = a P + b (mod 26), the
most frequently occurring letter is Q and the second most frequent is J.
(a) Break the cipher by determining the values of a and b.
[Hint: The most often used letter in English text is E, followed by T.]
(b) Write out the plaintext for the intercepted message WCPQ JZQO MX.
5. (a) Encipher the message HAVE A NICE TRIP using a Vigenère cipher with the keyword
MATH.
(b) The ciphertext BS FMX KFSGR JAPWL is known to have resulted from a Vigenère
cipher whose keyword is YES. Obtain the deciphering congruences and read the
message.
6. (a) Encipher the message HAPPY DAYS ARE HERE using the autokey cipher with
seed Q.
(b) Decipher the message BBOT XWBZ AWUVGK, which was produced by the autokey
cipher with seed RX.
7. (a) Use the Hill cipher
C1 = 5P1 + 2P2 (mod 26)
biopje
C2 = 3P¡ +4 P2 (mod 26)
to encipher the message GIVE THÊM TIME.
(b) The ciphertext ALXWU VADCOJO has been enciphered with the cipher
C1 = 4P1+11P2 (mod 26)
bo
Geft
-130
C2 = 3P1 + 8 P2 (mod 26)
Derive the plaintext.
8. A long string of ciphertext resulting from a Hill cipher
C1 = lc
a P1 + b P2 (mod 26)
our beuog
C2 = cP1+d P2 (mod 26)
coveeled that the most frequently occurring two-letter bl0cks were HO and PP, in that
order.
(a) Find the values of a, b, c, and d.
THint: The most common two0-letter biocks in the English language are TH, followed
(b) What is the plaintext for the intercepted meson
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 3 steps with 2 images
Recommended textbooks for you
Computer Networking: A Top-Down Approach (7th Edi…
Computer Engineering
ISBN:
9780133594140
Author:
James Kurose, Keith Ross
Publisher:
PEARSON
Computer Organization and Design MIPS Edition, Fi…
Computer Engineering
ISBN:
9780124077263
Author:
David A. Patterson, John L. Hennessy
Publisher:
Elsevier Science
Network+ Guide to Networks (MindTap Course List)
Computer Engineering
ISBN:
9781337569330
Author:
Jill West, Tamara Dean, Jean Andrews
Publisher:
Cengage Learning
Computer Networking: A Top-Down Approach (7th Edi…
Computer Engineering
ISBN:
9780133594140
Author:
James Kurose, Keith Ross
Publisher:
PEARSON
Computer Organization and Design MIPS Edition, Fi…
Computer Engineering
ISBN:
9780124077263
Author:
David A. Patterson, John L. Hennessy
Publisher:
Elsevier Science
Network+ Guide to Networks (MindTap Course List)
Computer Engineering
ISBN:
9781337569330
Author:
Jill West, Tamara Dean, Jean Andrews
Publisher:
Cengage Learning
Concepts of Database Management
Computer Engineering
ISBN:
9781337093422
Author:
Joy L. Starks, Philip J. Pratt, Mary Z. Last
Publisher:
Cengage Learning
Prelude to Programming
Computer Engineering
ISBN:
9780133750423
Author:
VENIT, Stewart
Publisher:
Pearson Education
Sc Business Data Communications and Networking, T…
Computer Engineering
ISBN:
9781119368830
Author:
FITZGERALD
Publisher:
WILEY