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 quality management system, Question: Quality management standar...

Question: Quality management standards are seen as a major pillar supporting the drive for continuous quality improvement through TQM. (a) What do you meant by the term ‘Qua

Explain how the key exchange algorithm works, Question: (a) Explain how...

Question: (a) Explain how the Diffie-Hellman key establishment protocol works. (b) Prove that the Diffie-Hellman key establishment protocol is vulnerable to a `man in the mi

Algorithm, algorithm on simple intrest

algorithm on simple intrest

Define broadcasting , Broadcasting is the distribution of video and audio...

Broadcasting is the distribution of video and audio content to a whole audience via any audio or visual mass communications medium, but generally one using electromagnetic radiat

Draw a suitable physical network diagram, Question a) From the capture ...

Question a) From the capture below: Give the datagram source IP address, upper layer protocol, Total length in decimal and header checksum in hexadecimal; the segment source po

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

Incident response, Incident Response: Complete the following sections as id...

Incident Response: Complete the following sections as identified from your Incident Response template (in MS Word format): Update the table of contents (autogenerated) Separate

Assignment, Hello i have submitted an assignment and i am still waiting to ...

Hello i have submitted an assignment and i am still waiting to know if it has been accepted or not the ref number is TicketID: EM201381BRY525CN, the due date is for monday 27th of

Project, Network diagram for a mediacal care

Network diagram for a mediacal care

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