Skip to Content
Introduction to Cryptography with Coding Theory, 3rd Edition
book

Introduction to Cryptography with Coding Theory, 3rd Edition

by Wade Trappe, Lawrence C. Washington
February 2020
Beginner
621 pages
19h 34m
English
Pearson
Content preview from Introduction to Cryptography with Coding Theory, 3rd Edition

4.6 Exercises

  1. Alice is learning about the shift cipher. She chooses a random three-letter word (so all three-letter words in the dictionary have the same probability) and encrypts it using a shift cipher with a randomly chosen key (that is, each possible shift has probability 1/26). Eve intercepts the ciphertext mxp.

    1. Compute P(M=catC=mxp). (Hint: Can mxp shift to cat?)

    2. Use your result from part (a) to show that the shift cipher does not have perfect secrecy (this is also true because there are fewer keys than ciphertexts; see the proposition at the end of the first section).

  2. Alice is learning more advanced techniques for the shift cipher. She now chooses a random five-letter word (so all five-letter words in the dictionary have the same ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

Applied Cryptography: Protocols, Algorithms and Source Code in C, 20th Anniversary Edition

Applied Cryptography: Protocols, Algorithms and Source Code in C, 20th Anniversary Edition

Bruce Schneier
Algorithms, 4th Edition

Algorithms, 4th Edition

Robert Sedgewick, Kevin Wayne
Serious Cryptography

Serious Cryptography

Jean-Philippe Aumasson

Publisher Resources

ISBN: 9780136758181