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

Encryption, How safe is the encryption of virtual private networks?

How safe is the encryption of virtual private networks?

Placeholders for the plaintext characters, Encode the following plaintext, ...

Encode the following plaintext, using the Caesar cipher:             LORD OF THE RINGS b) The following ciphertext              jw njbh lxmn cx kanjt has been encoded usi

Network security in an organisation, Network security is an issue for compa...

Network security is an issue for companies regardless of whether they participate in electronic commerce; however, since most organizations have a Web site that allows some interac

Growth of lan technology, GROWTH OF LAN TECHNOLOGY The production of s...

GROWTH OF LAN TECHNOLOGY The production of shared communication channels (LANs) started in 1960s and early 1970. The basic idea behind was to reduce the number of connectio

Develop firewall rules based on a fictitious organisation, Question requir...

Question requires you to develop firewall rules based on a fictitious organisation. Scenario: You work for a security-conscious company, xC-Cure, who develop encryption te

Explain rsa encryption, (a) Describe RSA encryption. (b) For an RSA encr...

(a) Describe RSA encryption. (b) For an RSA encryption the values of the primes are: p=29, q=31. select e=11, evaluate the public and private keys. (c) How can RSA be used fo

Nstissc security model, NSTISSC SECURITY MODEL The NSTISSC Security Model ...

NSTISSC SECURITY MODEL The NSTISSC Security Model provides a detailed perspective on security. While the NSTISSC model covers the 3 dimensions of information security, it removes

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

ITC 571 Emerging Technologies and Innovation Assignment, Ask quProject brie...

Ask quProject brief template The project brief is a document upon which the full Project Proposal and Plan will be based. About me: Who are you? What do you do? What is your Exper

Difference between a class profile and a child profile sheet, QUESTION ...

QUESTION (a) Mention two attitudes of a carer towards an inspector that could lead to negative outcomes (b) Give two performance indicators of Early Childhood Education that

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