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

Information asset classification-risk management, Information asset classif...

Information asset classification-risk management A number of organizations have data classification schemes (for instance confidential, internal, public data). The classificat

Name the various layers of the osi model, Problem (a) Name the various ...

Problem (a) Name the various layers of the OSI model. (b) Show, by means of a diagram, how  the TCP/IP  reference model  is different from the OSI-7 reference model? Why is

Explain transposition ciphers and substitution cipher, What do you understa...

What do you understand by cryptanalysis? Discuss about the transposition ciphers substitution cipher, and onetime pads. The messages which are intended to transmit secretly and

Kasonet pinging system, KASONet Pinging System: Project Title:       ...

KASONet Pinging System: Project Title:                                                           "KASONet Pinging System"   Brief Overview of Project: The o

What type of rfid tag is more appropriate for ws-pass, Consider the followi...

Consider the following case study: In order to avoid criticisms of their existing manned road-toll payment system on its private road, WS-Pass has decided to adopt an automated

Describe the two possible configurations for 3des, QUESTION (a) Describ...

QUESTION (a) Describe the two possible configurations for 3DES (b) What is the main disadvantage of 3DES? (c) Why are most modern symmetric algorithm block ciphers? (d

Configuration for 3des, (a) Explain the two possible configuration for 3DE...

(a) Explain the two possible configuration for 3DES. (b) What is the main disadvantage of 3DES? (c) Why are most modern symmetric algorithm block ciphers? (d) Describe

Cyber security - vulnerabilities, The world has to deal with newly released...

The world has to deal with newly released vulnerabilities on a daily basis.  These vulnerabilities eventually lead to active exploits of systems, and it is our job as cyber securit

Corresponding access control matrix, Consider a computer system with three ...

Consider a computer system with three users: Alice, Bob and Cindy. Alice owns the file alicerc, and Bob and Cindy can read it. Cindy can read and write the file bobrc, which Bob ow

Internet protocol(ip), Internet Protocol IP Gives computer-to-comp...

Internet Protocol IP Gives computer-to-computer communication. Host and receiver addresses are computers. This is also known machine-to-machine communication.

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