User Account

All Pages

ciphertext, Computer Network Security

Assignment Help:
Encode the following plaintext, using the Caesar cipher:

LORD OF THE RINGS
b) The following ciphertext

jw njbh lxmn cx kanjt

has been encoded using a generalised Caesar cipher where the following rule computes a character ci in the cipher text from a character pi in the plain text:

ci = E(pi) = pi + d

where d is a positive integer.

Find the number d and the plain text. Hint: use a table of English letter frequencies. This information can be found on the Internet.

c) Now consider the following cipher text:

homlox prv hetorx orxolxpersorx

A more general substitution cipher has been used. Recall that this means that every letter of the alphabet appearing in the plain text is replaced with another unique letter of the alphabet. For example, the letter ''a'' could be mapped into ''h'', the letter ''b'' into ''x'' etc. The ciphertext then simply consists of these mapped letters.
Work out the original plain text message, using the following approach:

(i) Write a line of dashes ("_") as placeholders for the plaintext characters corresponding to each letter in the above cipher text. Make sure you also mark the spaces between the different words as they will give you clues as soon as you know some of the letters.

(ii) Using the English letter frequency table, find the letter which the letter "e" is most likely to be replaced with. Use this to replace some of the "_" by the letter "e" (simply copy the last line you wrote and then replace).

Related Discussions:- ciphertext

Keystroke-based access control model, Suppose you are working for one of th...

Suppose you are working for one of the leading credit reporting agencies that manages users' credit rating info with different financial institutions.  The company wishes to implem

Function of key secrecy and algorithm secrecy in security, What is the func...

What is the function of key secrecy and algorithm secrecy in security?  Algorithm Secrecy is explained as follows: ‘Algorithm secrecy’ is a method of keeping an algorithm

Explain the term virtual private network, Question: (a) Besides privac...

Question: (a) Besides privacy, what other security functions does Pretty Good Privacy (PGP) provides? (b) What is the Post Office Protocol (POP) used for? Why is it impo

Cyber security - vulnerabilities, The world has to deal with newly released...

The world has to deal with newly released vulnerabilities on a daily basis.  These vulnerabilities eventually lead to active exploits of systems, and it is our job as cyber securit

Vulnerability scanners, VULNERABILITY SCANNERS Active vulnerability scan...

VULNERABILITY SCANNERS Active vulnerability scanners scan networks for detailed information, it initiate traffic to determine security holes. This scanner identifies usernames a

Mobile wireless networks , Is standard TCP effective in mobile wireless net...

Is standard TCP effective in mobile wireless networks that operate with the IEEE 802.11 wireless local area network protocol?Discuss the issue

Describe des encryption, (a) Describe DES encryption with a block diagram a...

(a) Describe DES encryption with a block diagram and brief steps. (b) How does triple DES improve security. What is the effective key length of triple DES? How can 3DES be compa

Explain web defacement, QUESTION (a) Compare and contrast phishing and ...

QUESTION (a) Compare and contrast phishing and pharming attacks (b) Nowadays, web defacement may not always be visual (i) Explain web defacement (ii) What is the main

Steganography-cryptography, Steganography It is a process of hiding info...

Steganography It is a process of hiding information in use for a long time. Most popular modern version of this process hides information within files appearing to contain digit

Base lining-information security, Base lining •    Organizations do not ...

Base lining •    Organizations do not have any contact to each other •    No two organizations are identical to each other •    The best practices are a moving target •    K

Write Your Message!

Captcha
Order Assignment

Featured Services

Order Now

Popular Subjects

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!

Submit Assignment

Academics

Major Subjects

Majors

Get In Touch

whatsapp: +91-977-207-8620

Phone: +91-977-207-8620

Email: [email protected]

TERMS & POLICIES

HELP & SUPPORT

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