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

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

Describe benefits of effective communication, Question: (a) Explain the...

Question: (a) Explain the following terms: Information Communication Technology, Operating System and Application Software. (b) Define what a computer is, give four anatomi

Describe the use of control channels in gsm network, Problem 1: What is...

Problem 1: What is the function of AUC in the GSM architecture? Explanation of HLR(AUC) Architecture of GSM Problem 2: Show the layered architecture of t

Cyclic redundancy check (crc), CYCLIC REDUNDANCY CHECK (CRC) To activa...

CYCLIC REDUNDANCY CHECK (CRC) To activate a network system to check move error without increasing the amount of information in every packet another most successful method is m

802.11 wireless lans and csma/ca, 802.11 WIRELESS LANs AND CSMA/CA:  ...

802.11 WIRELESS LANs AND CSMA/CA:  IEEE 802.11 is standard wireless LAN that needs radio signals at 2.4GHz. Its speed is 11Mbps. The older computers use radio signals at data

E-commerce, briefly expslain type of e-commerce

briefly expslain type of e-commerce

[email protected], Re: Website Google Ranking Hello! Hope yo...

Re: Website Google Ranking Hello! Hope you are doing well. I discovered some major issues in your website which might be the cause for the Google Penalties and poor search ranki

Computer security incident response team, QUESTION 1 Using a real life ...

QUESTION 1 Using a real life scenario or context list and set the scene for at least four advantages that an organized incident response program promotes. QUESTION 2 Yo

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