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

Network security keys, The three primary types of network protection are th...

The three primary types of network protection are the same as the three primary areas where a network can be attacked. Every network needs protection against people-related, hardwa

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

Rsa block and vernam stream ciphers, RSA Block and Vernam Stream Ciphers ...

RSA Block and Vernam Stream Ciphers This assignment involves writing two small Python scripts and a report. Before you start you must download the ?le summarysheets.zip from th

Emulation, In this section, you should create a program that emulates a GBN...

In this section, you should create a program that emulates a GBN node. Two GBN nodes will be running to send packets to each other through the UDP protocol. For emulation purpose,

Network security course work, doing coursework in Network Security to prese...

doing coursework in Network Security to present a possible solution to the problem at hand by creating a prototype of the new network security infrastructure. This new design shou

Looking for data network security assignment, I am ryan, i am looking for d...

I am ryan, i am looking for data security and network assignment help, Do you have experts in data security?

Develop a preliminary simulation model, Question: (a) State the strong ...

Question: (a) State the strong law of large numbers. (b) Data have been collected on response times (in minutes) at a fire station. The data are 2:7 1:8 0:8 1:4 1:2 (i

Explain authentication process in a synchronous token system, Question: ...

Question: (a) Explain briefly the PCI Control Objectives which enterprises must meet to be compliant with the Payment Card Industry Data Security Standard (PCI DSS). Specify a

Tracing a route, There is another probing methods i-e Trace Route. To get m...

There is another probing methods i-e Trace Route. To get more detail it is used     As given in the figure about the route to DANDELION-PATCH.MIT.EDU was looked out a

Pinging a web server, Ask quIf you are pinging a web server from a user’s c...

Ask quIf you are pinging a web server from a user’s client PC, how might the statistical information provided by ping be useful to you?estion #Minimum 100 words accepted#

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