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

Packet filtering firewall-stateless packet filtering, Stateless Packet Filt...

Stateless Packet Filtering Stateless or static packet filtering is the most straightforward kind of packet filtering that allows or disallows data transfer based on the addres

Risk determination, Risk Determination For purpose of relative risk asse...

Risk Determination For purpose of relative risk assessment, risk equals probability of vulnerability occurrence TIMES value MINUS percentage risk already controlled PLUS an elem

Complexity of network systems, Computer networks is a complex subject due t...

Computer networks is a complex subject due to the given reasons: MANY DIFFERENT TECHNOLOGIES EXIST: The first reason for the complexity of networks is that there are s

Threads and attacks-information security, THREADS AND ATTACKS Threat is ...

THREADS AND ATTACKS Threat is an object, person, or other entity which represents a constant danger to an asset. To make sound decisions about information security, management s

Implement security measures, Problem (a) Give two reasons for companie...

Problem (a) Give two reasons for companies to implement security measures. (b) What is the regulatory expectation regarding i. healthcare information, ii. financial

Programming, SDES encryption and decryption

SDES encryption and decryption

Half-duplex and full-duplex mode of transmission, Question: a. State br...

Question: a. State briefly three reasons why computer networks are used? b. Differentiate between simplex, half-duplex and full-duplex mode of transmission. c. State any

Draw the waveform for an asynchronous transmission, QUESTION: (a) For ...

QUESTION: (a) For the bit stream 010011, sketch the waveforms for each of the code indicated. Assume that the signal level for a space in NRZ-L is positive; the signal level f

Define multimedia and application of multimedia, Describe the salient featu...

Describe the salient features of the multimedia. Also explain the applications of it. Multimedia can be understood as follows: Multimedia is on the whole a media which makes

People, People,Procedures,Data Asset Identification-Risk Management Th...

People,Procedures,Data Asset Identification-Risk Management The human resources, data information and documentation assets are more difficult to identify. People having knowle

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