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

What is an autonomous system, QUESTION 1: a) Differentiate between a r...

QUESTION 1: a) Differentiate between a routing protocol and a routed protocol. b) Describe any three design goals of Routing protocols. c) Lists some of the features shared

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

Describe phishing attacks, QUESTION (a) (i) Describe Phishing attacks. ...

QUESTION (a) (i) Describe Phishing attacks. (ii) Distinguish between Phishing and Spear Phishing attacks. (b) Describe two instances where an attacker sniffing on a netwo

Computer network and internet, WHICH OF THE PRODUCT OF llc sublayer

WHICH OF THE PRODUCT OF llc sublayer

Derive the transmitted crc header checksum, QUESTION (a) Consider the f...

QUESTION (a) Consider the following digital bit stream 01001100 is to be encoded in: i. NRZ-I ii. Pseudoternary iii. Manchester iv. Differential Manchester Show th

Data units at different layers of the tcp/ ip protocol suite, Data units at...

Data units at different layers of the TCP/ IP protocol suite The data unit prepared at the application layer is known a message, at the transport layer the data unit build is

Traditional network design approach, Question: a) Give two reasons why ...

Question: a) Give two reasons why the building-block approach is favoured to the traditional network design approach. b) With reference to network monitoring parameters, dis

Provide a labelled drawing of a standard serial port, Question 1: (a) W...

Question 1: (a) With the help of a diagram show the basic structure of a computer system. (b) Explain as fully as you can each of the parts mentioned above. (c) What are

Identify possible controls-information security, Identify Possible Controls...

Identify Possible Controls For each threat and linked vulnerabilities which have residual risk, create primary list of control ideas. Residual risk is the risk which remains to

Extended euclidean algorithm, (a) Using the extended Euclidean algorithm, ...

(a) Using the extended Euclidean algorithm, find the multiplicative inverse of 504 mod 67. (b) Decrypt the following ciphertext, which has been encrypted using Caesar cipher:

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