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

Error reporting mechanism (icmp), ERROR REPORTING MECHANISM (ICMP) INT...

ERROR REPORTING MECHANISM (ICMP) INTRODUCTION:  IP gives best-effort delivery. Delivery causes can be ignored; datagrams may be 'dropped on the ground'. Internet Control Me

Inverse z transform, table for inverse z transform

table for inverse z transform

Topology, What is the concept of topology?

What is the concept of topology?

Hypothetical reliable data transfer protocol, Hypothetical reliable data tr...

Hypothetical reliable data transfer protocol: A jumping window based Go-back-N  ARQ protocol for file transfer using UDP as the transport protocol: In this protocol, a window o

Cyber security, How to pretect my computer from attacking

How to pretect my computer from attacking

Architecture of www named world wide web, Write down short notes on the arc...

Write down short notes on the architecture of WWW which is World Wide Web. WWW which means The World Wide web or the web is a repository of information spread worldwide and rel

What do you meant by the term diffusion and confusion, Question: (a) W...

Question: (a) What do you meant by the term diffusion and confusion? Explain how diffusion and confusion can be implemented. (b) Distinguish between authorisation and auth

Programming, SDES encryption and decryption

SDES encryption and decryption

Develop firewall rules based on a fictitious organisation, Question requir...

Question requires you to develop firewall rules based on a fictitious organisation. Scenario: You work for a security-conscious company, xC-Cure, who develop encryption te

Functional areas in network management, Question 1 a) Explain how CSMA...

Question 1 a) Explain how CSMA/CD works. b) Describe the term "exponential back-off". c) Describe the differences between "circuit switching" and "packet switching". d) Th

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