Find the possible deciphering transformations, Computer Network Security

Assignment Help:

Question:

(a) A string of ciphertext was enciphered using an a±ne transformation of single letters in a 28-letter alphabet consisting of A to Z, a blank and a?, where A to Z have numerical equivalents 0 to 25, blank=26, ?=27. A frequency analysis reveals that the the first, second and third most common letters of this ciphertext are B, ? and I, respectively. Suppose that the first and second most common letters in an English language text written in this 28-letter alphabet are ` '(blank) and E, respectively.

(i) Find the possible deciphering transformations.

(ii) Using the fact that T, is the third most common letter in the English language (of our 28 letters), find the right deciphering transformation.

(b) The ciphertext

¡GSTMTSI XJMUIGHRFKYMV

was generated using a 2£2 enciphering matrix with a 29¡letter alphabet, where A to Z have numerical equivalents 0 to 25, blank=26, !=27, and ¡ = 28. Given that the last five letters of the plaintext are A¡ONE, determine the complete plaintext.


Related Discussions:- Find the possible deciphering transformations

Explain how the diffie-hellman key agreement protocol works, (a) Using Fer...

(a) Using Fermat's theorem, find 3 201 mod 11. (b) Explain how the Diffie-Hellman key agreement protocol works and what its purpose and main properties are. Consider a Dif

Ring topology, RING TOPOLOGY In this topology of network the devices a...

RING TOPOLOGY In this topology of network the devices are connected to each other in packed loop. In this network first computer passes data packet to the second and then seco

Describe the role of dns root servers in network, QUESTION (a) Describ...

QUESTION (a) Describe the role of DNS root servers in the Internet network. (b) What do you understand by the handover concept in a mobile network? (c) List five meth

Base lining-risk management, Base lining •    Organizations do not have ...

Base lining •    Organizations do not have any contact to each other •    No two organizations are identical to each other •    The best practices are a moving target •    K

Explain the schemes for distribution of public keys, (a) What is a pseudora...

(a) What is a pseudorandom generator? Give an example describing how it works. (b) Explain the key components of a wireless network and their purpose. (c) Describe the authen

Explain security, W h a t do you understand by the terms security, netwo...

W h a t do you understand by the terms security, network security and information security? How network security and information security are connected? Security can be def

Short term scheduler, Short term Scheduler function , also shown as a disp...

Short term Scheduler function , also shown as a dispatcher runs most frequently, and creates the finest-grained decision of which program could run next. This scheduler is called

Cracking the Vigenere Cipher, The following message was enciphered with a V...

The following message was enciphered with a Vigenère cipher. aikiaawgfspxeppvjabjnivulfznzvkrlidamsmyamlvskniyffdpbwtnxsvvbtnamvltsefoeycztkomylmerkwrs deusjgecmzkwvnreeyp

Computer adaptive test, Project Name : Computer Adaptive Test Role ...

Project Name : Computer Adaptive Test Role : Day to Day interaction with Client. Involved in Requirement Gathering, Estimation.Involved with Stellent design and architectur

Digital certificates-cryptography, Digital Certificates Digital Certific...

Digital Certificates Digital Certificates are electronic document having key value and identifying information about entity which controls key. Digital signature which is attach

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