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

Ping command , In the early days when there were some dozen computers machi...

In the early days when there were some dozen computers machine on the network, it was done individually but now as we have looked that there are millions of computers on the intern

The major decision hierarchy for disclosing security problem, QUESTION ...

QUESTION The major decision hierarchy for disclosing security problems is if the problem is with the product owned by the business or if it is used by the business. Although th

What is triple key management scheme, Q. What is Triple Key Management Sche...

Q. What is Triple Key Management Scheme? The triple key management mechanism provides optimum security by enabling the use of two pre-deployed keys for each of the WS nodes, an

Biology, Ask question #Minimum 100 words are there non parasitic v...

Ask question #Minimum 100 words are there non parasitic viruses

Calculate the minimum required signal strength, Question 1: (a) (i) Ra...

Question 1: (a) (i) Radio waves are subject to several propagation problems. Name any three of them. (ii) A Wi-Fi receiver requires a signal power of 50mW to operate correc

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

Cryptographic hash functions, (a) (i) Bob has public RSA key (n = 77, e...

(a) (i) Bob has public RSA key (n = 77, e = 7). Show that Bob's private key is (d = 43). (ii) Alice wants to send the message m = 13 to Bob. She encrypts the message usi

Mastering the complexity of network system, To master the complexity one mu...

To master the complexity one must apply the given points. CONCENTRATE IN UNDERSTANDING THE CONCEPTS: Instead of details of wires used to connect computers to a specif

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

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