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

Components of an information system, COMPONENTS OF AN INFORMATION SYSTEM ...

COMPONENTS OF AN INFORMATION SYSTEM The components of an information system are software, data, hardware, people, procedures and Networks. These 6 components are critical to ena

Describe types of communication impairments, Question : (a) "Pulse Code...

Question : (a) "Pulse Code Modulation (PCM), as used in telephony, samples a signal at 8 kHz using 256 quantization levels". Outline how this scheme works with the help of ske

Evaluations, Evaluations, Assessment, and Maintenance of Risk Controls W...

Evaluations, Assessment, and Maintenance of Risk Controls When the control strategy has been implemented, it should be monitored and measured on an ongoing basis to determine ef

Discuss five alternative testing techniques, QUESTION Testing of a Busi...

QUESTION Testing of a Business Continuity Plan (BCP) does not need to be costly or to interrupt the daily operations of the business. The result of the test should also be look

Plaintext, how to encryt the data in plaintext cipher

how to encryt the data in plaintext cipher

define broadcast, In broadcast topology there are further two types 1) ...

In broadcast topology there are further two types 1) SATELLITE\RADIO 2) RING TOPOLOGY In a radio or satellite topology every computers are connected to each other via radio o

Ip Datagram, Size of Option field of an ip datagram is 20 bytes. What is th...

Size of Option field of an ip datagram is 20 bytes. What is the value of HLEN? What is the value in binary?

Minimum cost flow problem, QUESTION (a) A convex flow problem is a no...

QUESTION (a) A convex flow problem is a non linear network flow problem. Explain how a convex flow problem could be transformed into a Minimum Cost Flow problem. (b) Exp

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.

Marketing, what are the participant of marketing channal?

what are the participant of marketing channal?

Write Your Message!

Captcha
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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd