\[ \begin{align}\begin{aligned}\newcommand\blank{~\underline{\hspace{1.2cm}}~}\\% Bold symbols (vectors) \newcommand\bs[1]{\mathbf{#1}}\\% Poor man's siunitx \newcommand\unit[1]{\mathrm{#1}} \newcommand\num[1]{#1} \newcommand\qty[2]{#1~\unit{#2}}\\\newcommand\per{/} \newcommand\squared{{}^2} \newcommand\cubed{{}^3} % % Scale \newcommand\milli{\unit{m}} \newcommand\centi{\unit{c}} \newcommand\kilo{\unit{k}} \newcommand\mega{\unit{M}} % % Percent \newcommand\percent{\unit{\%}} % % Angle \newcommand\radian{\unit{rad}} \newcommand\degree{\unit{{}^\circ}} % % Time \newcommand\second{\unit{s}} \newcommand\s{\second} \newcommand\minute{\unit{min}} \newcommand\hour{\unit{h}} % % Distance \newcommand\meter{\unit{m}} \newcommand\m{\meter} \newcommand\inch{\unit{in}} \newcommand\foot{\unit{ft}} % % Force \newcommand\newton{\unit{N}} \newcommand\kip{\unit{kip}} % kilopound in "freedom" units - edit made by Sri % % Mass \newcommand\gram{\unit{g}} \newcommand\g{\gram} \newcommand\kilogram{\unit{kg}} \newcommand\kg{\kilogram} \newcommand\grain{\unit{grain}} \newcommand\ounce{\unit{oz}} % % Temperature \newcommand\kelvin{\unit{K}} \newcommand\K{\kelvin} \newcommand\celsius{\unit{{}^\circ C}} \newcommand\C{\celsius} \newcommand\fahrenheit{\unit{{}^\circ F}} \newcommand\F{\fahrenheit} % % Area \newcommand\sqft{\unit{sq\,\foot}} % square foot % % Volume \newcommand\liter{\unit{L}} \newcommand\gallon{\unit{gal}} % % Frequency \newcommand\hertz{\unit{Hz}} \newcommand\rpm{\unit{rpm}} % % Voltage \newcommand\volt{\unit{V}} \newcommand\V{\volt} \newcommand\millivolt{\milli\volt} \newcommand\mV{\milli\volt} \newcommand\kilovolt{\kilo\volt} \newcommand\kV{\kilo\volt} % % Current \newcommand\ampere{\unit{A}} \newcommand\A{\ampere} \newcommand\milliampereA{\milli\ampere} \newcommand\mA{\milli\ampere} \newcommand\kiloampereA{\kilo\ampere} \newcommand\kA{\kilo\ampere} % % Resistance \newcommand\ohm{\Omega} \newcommand\milliohm{\milli\ohm} \newcommand\kiloohm{\kilo\ohm} % correct SI spelling \newcommand\kilohm{\kilo\ohm} % "American" spelling used in siunitx \newcommand\megaohm{\mega\ohm} % correct SI spelling \newcommand\megohm{\mega\ohm} % "American" spelling used in siunitx % % Inductance \newcommand\henry{\unit{H}} \newcommand\H{\henry} \newcommand\millihenry{\milli\henry} \newcommand\mH{\milli\henry} % % Power \newcommand\watt{\unit{W}} \newcommand\W{\watt} \newcommand\milliwatt{\milli\watt} \newcommand\mW{\milli\watt} \newcommand\kilowatt{\kilo\watt} \newcommand\kW{\kilo\watt} % % Energy \newcommand\joule{\unit{J}} \newcommand\J{\joule} % % Composite units % % Torque \newcommand\ozin{\unit{\ounce}\,\unit{in}} \newcommand\newtonmeter{\unit{\newton\,\meter}} % % Pressure \newcommand\psf{\unit{psf}} % pounds per square foot \newcommand\pcf{\unit{pcf}} % pounds per cubic foot \newcommand\pascal{\unit{Pa}} \newcommand\Pa{\pascal} \newcommand\ksi{\unit{ksi}} % kilopound per square inch \newcommand\bar{\unit{bar}} \end{aligned}\end{align} \]

Oct 24, 2024 | 310 words | 3 min read

10.2.2. Task 2

Learning Objectives

• Understand and implement different cipher algorithms for encrypting messages.

• Convert text strings to binary strings.

Task Instructions

Save the flowcharts for each of your tasks in tp2_team_teamnumber.pdf You will also need to include these flowcharts in your final report.

Create a function that uses the Vigenère cipher to encrypt a string. The function should take two arguments: the plaintext message to be encrypted and the key. It should return the encrypted ciphertext message. You can find details on this cipher in Vigenère Cipher.

Next, create a function that takes a message string, a starting sequence string, and an ending sequence string as arguments. It should generate and return a single binary string that consists of the starting sequence, followed by the message, and then by the ending sequence, all converted to binary strings. For example, with a starting sequence of “0”, a message string “Hi”, and an ending sequence “1”, the function would convert the starting sequence to “00110000”, the message to “01001000 01101001”, and the ending sequence to “00110001”. The function would then return “00110000 01001000 01101001 00110001”.

Finally, create a main function in your Python program that uses the functions described above to encrypt a message, and then convert the ciphertext into a binary message. Your main function should prompt the user to enter a plaintext message, a key, a start sequence, and an end sequence, and then display both the ciphertext and the binary message.

Save your program as tp2_team_2_teamnumber.py.

Sample Output

Use the values in Table 10.33 below to test your program.

Table 10.33 Test Cases

Case	plaintext	key	start sequence	end sequence
1	Hi	secret	0	1
2	eng 133	secret	7	7
3	eng 133	SECRET	7	7
4	ENG 133	secret	007	700

Ensure your program’s output matches the provided samples exactly. This includes all characters, white space, and punctuation. In the samples, user input is highlighted like this for clarity, but your program should not highlight user input in this way.

Case 1 Sample Output

$ python3 tp2_team_2_teamnumber.py Enter the plaintext you want to encrypt: Hi Enter the key for Vigenere cipher: secret Enter the start sequence: 0 Enter the end sequence: 1 Encrypted Message using Vigenere Cipher: Zm Binary output message: 00110000 01011010 01101101 00110001

Case 2 Sample Output

$ python3 tp2_team_2_teamnumber.py Enter the plaintext you want to encrypt: eng 133 Enter the key for Vigenere cipher: secret Enter the start sequence: 7 Enter the end sequence: 7 Encrypted Message using Vigenere Cipher: wri 521 Binary output message: 00110111 01110111 01110010 01101001 00100000 00110101 00110010 00110001 00110111

Case 3 Sample Output

$ python3 tp2_team_2_teamnumber.py Enter the plaintext you want to encrypt: eng 133 Enter the key for Vigenere cipher: SECRET Enter the start sequence: 7 Enter the end sequence: 7 Encrypted Message using Vigenere Cipher: wri 521 Binary output message: 00110111 01110111 01110010 01101001 00100000 00110101 00110010 00110001 00110111

Case 4 Sample Output

$ python3 tp2_team_2_teamnumber.py Enter the plaintext you want to encrypt: ENG 133 Enter the key for Vigenere cipher: secret Enter the start sequence: 007 Enter the end sequence: 700 Encrypted Message using Vigenere Cipher: WRI 521 Binary output message: 00110000 00110000 00110111 01010111 01010010 01001001 00100000 00110101 00110010 00110001 00110111 00110000 00110000