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

Explain what is software debouncing, Question : (a) How does a 2-key r...

Question : (a) How does a 2-key rollover differ from the N-key rollover? (b) Why is isolation so important in interfacing? (c) Explain what is software debouncing.

Cashckcdjsc, bewcsmcbnmdc sdmcbh

bewcsmcbnmdc sdmcbh

Describe des encryption, (a) Describe DES encryption with a block diagram a...

(a) Describe DES encryption with a block diagram and brief steps. (b) How does triple DES improve security. What is the effective key length of triple DES? How can 3DES be compa

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

Inverse z transform, table for inverse z transform

table for inverse z transform

Advantages and disadvantage of packet filtering firewall, Advantages and Di...

Advantages and Disadvantage of Packet Filtering firewall   Advantages One screening router can help protect entire network One key advantage of packet filter

Explain how the diffie-hellman key agreement protocol works, (a) Using Fer...

(a) Using Fermat's theorem, find 3 201 mod 11. (b) Explain how the Diffie-Hellman key agreement protocol works and what its purpose and main properties are. Consider a Dif

Risk control strategies-risk management, Risk Control Strategies Once th...

Risk Control Strategies Once the ranked vulnerability risk worksheet has created, they should choose one of following 4 strategies to control each risk: •    Apply safeguards wh

Perimeter network security system, Title: Perimeter Network Security System...

Title: Perimeter Network Security System Outline Requirements The University is based in Glasgow, and provides higher education services to its students and staff. It is loc

X.509, Consider the details of the X.509 certificate shown below. a. Identi...

Consider the details of the X.509 certificate shown below. a. Identify the key elements in this certificate, including the owner''s name and public key, its validity dates, the nam

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