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

Hybrid cryptography systems-cryptography, Hybrid Cryptography Systems Th...

Hybrid Cryptography Systems This makes use of different cryptography systems. Except digital certificates, pure asymmetric key encryption is not used extensively. Asymmetric enc

Using Technology as Experience Framework, Write a two to three (2-3) page p...

Write a two to three (2-3) page paper in which you: Explain how the Web user interfaces help donors to make decisions. Relate the emotional thread demonstrated in the case study to

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

Explain the approaches to lric modeling, (a) Cost allocation mechanisms ar...

(a) Cost allocation mechanisms are important when it comes to establishing other aspects of inter-firm compensations and how these are transferred to the users. There are two pri

Explain how ethernet deals with collisions, (a) Describe how CSMA/CD operat...

(a) Describe how CSMA/CD operates and explain how Ethernet deals with collisions. (b) Describe how the subsequent protocols work: i. ARP ii. DHCP iii. DNS iv. SMTP (c) The

Udp datagram format, UDP DATAGRAM FORMAT: It is given in the figure be...

UDP DATAGRAM FORMAT: It is given in the figure below:

Http protocol, Question (a) Name 3 popular electronic mail access prot...

Question (a) Name 3 popular electronic mail access protocols? (b) i. What is DNS? ii. Briefly, describe what it does and how it works? iii. Why does DNS use a dist

Emerging threats related to use of networks, Question requires you to submi...

Question requires you to submit a proposal based on the research report topic you will be addressing in the second assignment.  Note:  before commencing research on the topic, y

Explain the operation of the matchmaker middle agent, Question 1: (a) E...

Question 1: (a) Explain the operation of the "matchmaker" middle agent. (b) Describe why broker middle agents are more efficient in terms of the time taken for a service to

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

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