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 belady''s anomaly, Belady's Anomaly Also known FIFO anomaly. G...

Belady's Anomaly Also known FIFO anomaly. Generally, on raising the number of frames given to a process' virtual storage, the program execution is faster, because lesser page

Fragmentation and path mtu, FRAGMENTATION AND PATH MTU IPv6 source is ...

FRAGMENTATION AND PATH MTU IPv6 source is responsible for fragmentation. Routers simply drop datagrams bigger than network MTU. So source have to fragment datagram to arrive d

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

Policy management-information security, POLICY MANAGEMENT Policies should...

POLICY MANAGEMENT Policies should be managed as they constantly change. Good policy development and maintenance make a more resilient organization. All policies undergo tremendou

Types of errors detection in crc , CRC can detect the following errors bett...

CRC can detect the following errors better than check sums. a) Vertical errors b) Burst errors a) VERTICAL ERRORS:  This kind of error happens due to a hardware fai

Describe how a cellular network works, Problem 1 . Show various features of...

Problem 1 . Show various features of a 1G network Total three features for each feature of 1G Problem 2. Describe how a cellular network works with functional block diagram

Cyber troll case, According to the case, The EZ Company introduced a new te...

According to the case, The EZ Company introduced a new technology, focusing on the principles of informationintegration and visualization. The company started negotiatinga saleto a

Benchmarking-information security, Benchmarking An alternative approach to...

Benchmarking An alternative approach to risk management is Benchmarking. It is process of seeking out and studying practices in other organizations which one’s own organization de

Securing the components-information security, SECURING THE COMPONENTS Co...

SECURING THE COMPONENTS Computer can be subject of an attack or the object of an attack. When subject of an attack, computer is used as lively tool to conduct attack. The figure

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 (

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