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

Representation of a tcp header, (a) Figure is a representation of a TCP hea...

(a) Figure is a representation of a TCP header. For each of the fields lettered from A to G, state the name of the field and provide a brief explanation for the function of each fi

Explain how ftp works, QUESTION (a) FTP is a protocol used for the de...

QUESTION (a) FTP is a protocol used for the delivery of files across networks. Explain how FTP works (support your answer with a diagram). (b) How does TCP perform the gi

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

English language, how can i talk English fast

how can i talk English fast

Data units at different layers of the tcp/ ip protocol suite, Data units at...

Data units at different layers of the TCP/ IP protocol suite The data unit prepared at the application layer is known a message, at the transport layer the data unit build is

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

Find the capacity of the wcdma, Question: (a) Describe the term interfe...

Question: (a) Describe the term interference in the space, time, frequency, and code domain. (b) Consider a 1 G - AMPS: 824-849 MHz (forward) ; 869-894 MHz (reverse). B

Network management system, Question (a) Draw a typical hybrid star-rin...

Question (a) Draw a typical hybrid star-ring topology paying attention to how the clients and switching hubs are connected. (b) State 3 main differences between a router

What do you understand by demilitarized zone, Problem 1: What does the ...

Problem 1: What does the SNMP access policy show? SNMP community diagram SNMP access policy Problem 2: Does there exist any formal functional specificat

Summarises the firewall protocols, Your rules should ensure that Internet a...

Your rules should ensure that Internet access will be restricted to the following: Only the following services will be permitted as OUTBOUND traffic (to the Internet from the DM

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