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

Computer adaptive test, Project Name : Computer Adaptive Test Role ...

Project Name : Computer Adaptive Test Role : Day to Day interaction with Client. Involved in Requirement Gathering, Estimation.Involved with Stellent design and architectur

Programming, For this assignment you will create a program called MMWordFix...

For this assignment you will create a program called MMWordFix (Multi-Mode WordFix). This program prompts the user to select one of three word filters (uppercase, lowercase, encryp

Assignment, Hello i have submitted an assignment and i am still waiting to ...

Hello i have submitted an assignment and i am still waiting to know if it has been accepted or not the ref number is TicketID: EM201381BRY525CN, the due date is for monday 27th of

Provide the network configuration, QUESTION: a) Below is a capture of a...

QUESTION: a) Below is a capture of an Ethernet II frame which has an IPv4 packet and a segment. Provide the source MAC address in hexadecimal; the source IP address, the length

What do you understand by environmental accounting, Question : Environm...

Question : Environmental Accounting is a means for businesses to fulfill their responsibilities for accountability to stakeholders. (a) What do you understand by Environment

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

Looking for data network security assignment, I am ryan, i am looking for d...

I am ryan, i am looking for data security and network assignment help, Do you have experts in data security?

Calculate the false rejection, Divide the user data into 6 equal sets. Use ...

Divide the user data into 6 equal sets. Use the first set for the enrollment phase of your system, and the rest for the verification phase. Use the following formula to calculate t

Structure of a typical frame relay, Problem a) Consider a 1000 Mbps Eth...

Problem a) Consider a 1000 Mbps Ethernet with a single Store-N-Forward switch mid-way in the path between two nodes A and B. Assume that there are no other nodes on the network

Audit or review of the information security issues, Using the selected appr...

Using the selected approach, you should then conduct an audit or review of the information security issues associated with the use of computing facility and report on the findings.

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