Cryptography-sub cipher | Computer Science homework help

Computer Science

A character sub was used. Can you decipher as much of this text as you can? Submit your results in the dropbox. You may use Python to code the solution.

ztrfqvdjrzqt
rci wzyabi wdmwrzrdrzqt jzacif zw g jzacif rcgr cgw miit zt dwi hqf ygtx cdtvfivw qh xigfw (gt iojibbitr czwrqfx zw lzsit zt wzyqt wztlcw ‘rci jqvi mqqk’). zr mgwzjgbbx jqtwzwrw qh wdmwrzrdrztl isifx abgztrior jcgfgjrif hqf g vzhhifitr jzacifrior jcgfgjrif. zr vzhhifw hfqy rci jgiwgf jzacif zt rcgr rci jzacif gbacgmir zw tqr wzyabx rci gbacgmir wczhriv, zr zw jqyabiribx udymbiv.

rci wzyabi wdmwrzrdrzqt jzacif qhhifw sifx bzrrbi jqyydtzjgrzqt wijdfzrx, gtv zr pzbb mi wcqpt rcgr zr jgt mi igwzbx mfqkit isit mx cgtv, iwaijzgbbx gw rci yiwwgliw mijqyi bqtlif (yqfi rcgt wisifgb cdtvfiv jzacifrior jcgfgjrifw).

 

Understanding and Breaking Sub cipher

One way to break a substitution cipher is to use frequency analysis. Let’s focus on the English language for now but the process works the same way for other languages.  The character “e” occurs 12.7% in the Eglish language and the letter “t” occurs 9.35% and the letter “a” is 8.2% of the time.  So, you can count each character in the ciphered text, compute its frequency and start replacing it.  After you complete the first say 4 characters, you may want to change your strategy.  Can you explain why you want to stop after the first 4 characters? The two-character “of” is about 4.16% and “to” is about 2%.  Now try three characters frequency. 

After a period of time, you will be able to decipher most of the text.  I am going to ask you to do your first significant homework using frequency analysis.

One possibility for the substitution cipher:

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

V

J

Z

B

G

N

F

E

P

L

I

T

M

X

D

W

K

Q

U

C

R

Y

A

H

S

O

Note that we can have 25 factorial of these possibilities (remember 2^88 – 28-bit key)

Calculate the price of your order

Select your paper details and see how much our professional writing services will cost.

We`ll send you the first draft for approval by at
Price: $36
  • Freebies
  • Format
  • Formatting (MLA, APA, Chicago, custom, etc.)
  • Title page & bibliography
  • 24/7 customer support
  • Amendments to your paper when they are needed
  • Chat with your writer
  • 275 word/double-spaced page
  • 12 point Arial/Times New Roman
  • Double, single, and custom spacing
  • We care about originality

    Our custom human-written papers from top essay writers are always free from plagiarism.

  • We protect your privacy

    Your data and payment info stay secured every time you get our help from an essay writer.

  • You control your money

    Your money is safe with us. If your plans change, you can get it sent back to your card.

How it works

  1. 1
    You give us the details
    Complete a brief order form to tell us what kind of paper you need.
  2. 2
    We find you a top writer
    One of the best experts in your discipline starts working on your essay.
  3. 3
    You get the paper done
    Enjoy writing that meets your demands and high academic standards!

Samples from our advanced writers

Check out some essay pieces from our best essay writers before your place an order. They will help you better understand what our service can do for you.

Get your own paper from top experts

Order now

Perks of our essay writing service

We offer more than just hand-crafted papers customized for you. Here are more of our greatest perks.

  • Swift delivery
    Our writing service can deliver your short and urgent papers in just 4 hours!
  • Professional touch
    We find you a pro writer who knows all the ins and outs of your subject.
  • Easy order placing/tracking
    Create a new order and check on its progress at any time in your dashboard.
  • Help with any kind of paper
    Need a PhD thesis, research project, or a two-page essay? For you, we can do it all.
  • Experts in 80+ subjects
    Our pro writers can help you with anything, from nursing to business studies.
  • Calculations and code
    We also do math, write code, and solve problems in 30+ STEM disciplines.

Frequently asked questions

Get instant answers to the questions that students ask most often.

See full FAQ
    See full FAQ

    Take your studies to the next level with our experienced specialists

    Chat
    Chat
    Hello, we are online 24/7. Leave a message we will reply instantly