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 the close procurement project process, Question 1: Why do we ne...

Question 1: Why do we need a Law of Contract? a Explanation Reasons to have a law of contract b Explain the close procurement project process - Explanation (causes,

Describe the five-layer network using block diagrams, Problem 1: a) One...

Problem 1: a) One of the limitations of file processing systems is data inconsistency. Briefly explain with the help of an example what do you understand by this phrase. b)

Access control matrix, You are provided with 3000 sample keystrokes for 5 u...

You are provided with 3000 sample keystrokes for 5 users mentioned above. You can find this data using the ‘Lab 2 User Data' link in the ‘Lab 2' folder on Blackboard. Please note t

Describe the function of a tap in wmns, Question: (a) A Wireless Mesh N...

Question: (a) A Wireless Mesh Network (WMN) is a communications network made up of radio nodes organized in a mesh topology. i. Describe the function of a TAP in WMNs. ii.

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

Arp message format, ARP MESSAGE FORMAT Although the ARP data packet fo...

ARP MESSAGE FORMAT Although the ARP data packet format is sufficiently general to allow hardware addresses and arbitrary protocol. ARP is almost usually used to bind a 32-bit

Describe how the encapsulated security header protocol, Question: (a) ...

Question: (a) Give 2 benefits of using IPsec. (b) IPSec uses two protocol for security: Authentication Header protocol (AH) and the Encapsulated Security Header Protocol (

Mastering the complexity of network system, To master the complexity one mu...

To master the complexity one must apply the given points. CONCENTRATE IN UNDERSTANDING THE CONCEPTS: Instead of details of wires used to connect computers to a specif

Explain about structure of management information, Question 1 a) What is a...

Question 1 a) What is a NMS? Question 2 Explain about Structure of Management Information Question 3 A)In which UDP port number does a protocol entity receive message?

Write a note on digital signature, Question 1 Explain the types of threats...

Question 1 Explain the types of threats (Attacks) Question 2 What are the Characteristics of Good Encryption Technique? Question 3 Write a note on Digital Signatur

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