What is the unicity point of the cipher

Assignment Help Computer Network Security
Reference no: EM131248940

Homophonic cipher:-

Suppose that a language using an alphabet of J letters has the property that the i-th letter has a frequency of ki/N, for each i, where the ki's and N are integers with

A homophonic cipher is made up of exactly N symbols, with ki of these assigned to the i-th letter of the alphabet (and with no duplications). When a letter i is to be encrypted, one of the ki cipher symbols assigned to it is chosen at random. This will make all N code symbols appear with probability 1/N. To determine the unicity point of such a code, it is necessary to modify the basic relation for H(K|C) because H(C|M,K) is not zero.

(a) Show that in general

(b) Show that for the situation of this exercise

(c) If the language has an entropy determined only by the frequency of its letters, can the homophonic cipher be broken?

(d) The number of ways of assigning symbols for this cipher is

If the entropy of the language is H per letter, what is the unicity point of the cipher?

(e) Assuming that the entropy of English is 1.5 bits/letter and that the homophonic code of 100 symbols in the text is used, what is the unicity point? (Note that log W = 377.)

Reference no: EM131248940

Questions Cloud

Compare the forecast values with the actual values : In Section 13.9 you were introduced to the Schwarz criterion to determine lag length. How would you use this criterion to determine the appropriate lag length in a VAR model? Using the data on PCE and PDI given in Table 21.1, develop a bivariate V..
Define terms subject matter and personal jurisdiction : Explain the 3 different types of personal jurisdiction, which you have learned from your reading, research, and lectures. The three types of personal jurisdiction are personam jurisdiction, in rem jurisdiction, and quasi in rem jurisdiction. Provi..
Describe your process and the items you uncovered : Describe your process and the items you uncovered during your review. In a few sentences, explain how you will correct the issues and ask questions if you need help or advice
Business forms under consideration best : Advise Shania on which of the business forms under consideration best accomplishes her business goals. Thoroughly explain the reasons for your recommendation.
What is the unicity point of the cipher : Assuming that the entropy of English is 1.5 bits/letter and that the homophonic code of 100 symbols in the text is used, what is the unicity point?
Create written work utilizing concepts of critical thinking : Identify the informal fallacies, assumptions, and biases involved in manipulative appeals and abuses of language. Create written work utilizing the concepts of critical thinking.
Write about the theme of death by making connections : Write two to three paragraphs essay: About the theme ( Death) - write about the theme of Death by making connections between these two readings, and how was death in those two readings. in 2-3 simple small paragraphs.
Case for violence in an effective and persuasive way : In an essay of 300 words or more, explain whether you think Jones has made the case for violence in an effective and persuasive way. If so, what is it about his article that makes it effective and persuasive? If it is not, where do the problems li..
Is there a unit root in this time series : On the basis of these results, is the housing starts time series stationary or no stationary? Alternatively, is there a unit root in this time series? How do you know?

Reviews

Write a Review

Computer Network Security Questions & Answers

  Implementing information systems security policies

Describe the roles and responsibilities of those implementing information systems security policies.

  Write down a class code that outputs a security code the

question 1 write a class called message that prompts the user to enter a message of three words as one string where

  Determine impact of at least five potential logical threats

Determine the impact of at least five (5) potential logical threats that require attention. Detail the security controls (i.e., administrative, preventative, detective, and corrective) that the pharmacy could implement in order to protect it from ..

  Explain how you would use the information in item selected

Explain how you would use the information in the item selected with a client or organization. Describe the types of clients or organizations that would benefit from this information. Why did you choose this item?

  What security functions are typically outsourced

What security functions are typically outsourced?

  Computer security models

Use the Internet to research the following computer security models: Biba (Biba Integrity Model), Give a brief synopsis of each model in your own words. Please cite any references that you use to complete this assignment

  How security can be configured and provide configuration

Describe how the security can be configured, and provide configuration examples (such as screen-shots and configuration files). Marks are based on demonstrating technical detail and understanding, and choice of examples.

  Unique characteristics of the russian culture

What are some unique characteristics of the Russian culture that make cyberspace issues more challenging - do Russia and China do enough in the cyberspace area?

  Write the enterprise technical infrastructure security plan

Write one page with references in APA format.Utilizing your comprehensive security plan outline as a guide (It is the attached document), write the enterprise technical infrastructure security plan for the organization.

  Implement network security on edge routers

Implement network security on edge routers and LAN switches  and provide evidence that it is secure.

  Understanding on network-related issues

CISC650 Computer Networks - In order to show understanding on network-related issues, each student is expected to complete a paper on a relevant network topic of the students choosing and interest.

  Encrypt the plaintext by using vigenere cipher

Encrypt the following Plaintext using Vigenere cipher: Plaintext: stocks market is falling Key : one. Is Vigenere cipher monoalphabetic or polyalphabetic? Why?

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