Write a program to decrypt encrypted messages, Programming Languages

Assignment Help:

You are working for a cryptography department, where one of your jobs is to decipher intercepted messages that have been encrypted using a book cipher. The messages are sent by different people, each of whom writes their plaintext in a different language to confuse any attempt to decipher the messages. But this has made them a little too confident, and you have discovered a very useful secret: unaware that their messages can be cracked, each sender tends to use the same book passage over and over; all that changes is where in that passage they start the encryption. Being very lazy, they always start the encryption within 20 letters of the start of the passage. So for the purposes of this task, the 'key' is simply the starting position in the book text, and is a number from 0 to 20. Your job now is to write a computer program (a real executable program, not a spreadsheet) that can be used to decrypt these intercepted messages. The program will be required to read the ciphertext from a file and to display the plaintext on the screen, along with the key that was used to encrypt it. You will be asked to demonstrate your program to the tutor in the lab class on the due date. This is so that you will be there to run the program and make any decisions that need making. You will be given several ciphertexts to practice on, but in the demonstration you will be asked to demonstrate your program on files you have not seen. You may write your program in whatever programming language you wish.


Related Discussions:- Write a program to decrypt encrypted messages

System flowchart, creating system flowchart for website

creating system flowchart for website

Java interfaces, Expertsmind brings you unique solution in java assignment...

Expertsmind brings you unique solution in java assignments Interfaces A program in the Java selection language is a fuzzy type that is used to specify a program (in the ge

Assembly language programm , these 8 numbers (15, 20, 25, 30, 35, 40, 45, a...

these 8 numbers (15, 20, 25, 30, 35, 40, 45, and 50) with using conditional jump

Pascal program, Pascal program: Exactly what you need to do to generat...

Pascal program: Exactly what you need to do to generate your empirical data is specific to your individual assignment. However, some rules apply to all of you: 1. The gener

Vb assignment, Design an application that opens and analyses word files. R...

Design an application that opens and analyses word files. Requirements: Create an application that analyses text documents. It should open a text file, read each word into an ap

Fileless document and encryption(stegnography), code for using tree view co...

code for using tree view control and fill it with database

Kinect help, My kinect hand cursor only works for main menu but when it go...

My kinect hand cursor only works for main menu but when it goes to another page it wouldn''t work.. especially when there is for camera feed

Jsp - quiz, JSP QUIZ ASSIGNMENT SHOULD BE FUNCTIONAL ON ECLIPSE QUIZ HAS ...

JSP QUIZ ASSIGNMENT SHOULD BE FUNCTIONAL ON ECLIPSE QUIZ HAS TOTAL 20 QUESTIONS REGARDING VARIOUS CAPITALS OF COUNTRIES. WELCOME PAGE OFFERS USER TO ENTER HIS NAME. THEN USER C

Java, what is the difference between class and interface

what is the difference between class and interface

Difference between java and j2ee programming, Difference between java and j...

Difference between java and j2ee programming In the basic form, the phrase java is placed as a selection terminology. On the other hand, the phrase J2EE is placed as a renderin

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd