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

Different architectures for wireless networks, (a) What are the different a...

(a) What are the different architectures for wireless networks? (b) Explain how WEP authentication and encryption works, describe the vulnerability. (c) In what ways are secu

Bus topology, In BUS topology every computer is directly connected to p...

In BUS topology every computer is directly connected to primary network cable in a single way. Bus networks are the easiest way to connect multiple users, but can have problems

Firewall analysis tools-information security, FIREWALL ANALYSIS TOOLS Th...

FIREWALL ANALYSIS TOOLS There are a number of tools automate remote discovery of firewall rules and assist the administrator in analyzing rules Administrators who feel wary of u

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

Ucsf medical center case study-information security, Example : UCSF Medical...

Example : UCSF Medical Center In the year 2002, the University of California, San Francisco (UCSF) Medical Center received an email message from someone who claimed to be a doct

Sending an arp message, Normal 0 false false false EN-U...

Normal 0 false false false EN-US X-NONE X-NONE

Describe the functioning of cloud computing, Question 1:  Describe the ...

Question 1:  Describe the functioning of cloud computing. Question 2: Discuss on "Platform as a Service". Question 3: Discuss the steps involved in effective co

Explain briefly the role of the physical layer, a) Calculate the CRC for th...

a) Calculate the CRC for the frame below: Frame: 1101011011 Generator: 10011 Message after appending 4 zero bits: 11010110110000 b) OSI refers to a system in which any

Describe the procedure known as byte stuffing, Question: (a) For the b...

Question: (a) For the bit stream 010011, sketch the waveforms for each of the code indicated. Assume the following: the signal level for the previous bit for NRZI was a 1

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