تشفير الرسالة - كتاب الأمن السيبراني - الصف 12 - الفصل 1 - المملكة العربية السعودية

تم إزاحتها بمقدار 24 موضعًا) لتصبح "J". تم إزاحتها بمقدار 10 مواضع) لتصبح "V". تم إزاحتها بمقدار 4 مواضع) لتصبح "S". وفي هذه الحالة فإن كلمة "HELLO" المشفرة بواسطة خوارزمية تشفير فيجنر وباستخدام الكلمة المفتاحية "KEY" تصبح "RIJVS". لفك تشفير الرسالة، يتم إجراء العملية العكسية ليتم إزاحة كل حرف في "RIJVS" إلى الخلف بالمقدار المحدد للحرف المقابل في الكلمة الأساسية "KEY". --- SECTION: تشفير الرسالة --- (Encrypting the Message) def vigenere_encrypt(plaintext, keyword): # Calculate the length of the keyword keyword_length = len(keyword) # Convert each character in the keyword to its ASCII value keyword_as_int = [ord(i) for i in keyword] # Convert each character in the plaintext to its ASCII value يمثل نظام آسكي (ASCII) نظام ترميز يتكون من مجموعة رموز قياسية تمثل جميع الأحرف الأبجدية الرقمية الإنجليزية. وزارة التعليم 121 Ministry of Education 2025 - 1447 --- VISUAL CONTEXT --- **TABLE**: Vigenere Cipher Table (Shift 24) Description: A 26x26 Vigenere cipher table showing the English alphabet. The first row and column are the standard alphabet A-Z. Each subsequent row is a Caesar cipher shift of the previous row. In this specific example, the letter 'L' (from the plaintext/row) is highlighted in orange, and the letter 'Y' (from the key/column) is highlighted in green. Their intersection, the letter 'J', is highlighted in red, indicating the result of a 24-position shift. Table Structure: Headers: 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 Rows: Row 1: 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 Row 2: 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 Row 3: 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 | A Row 4: C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B Row 5: D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C Row 6: E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D Row 7: F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E Row 8: G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F Row 9: H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G Row 10: I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H Row 11: J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I Row 12: K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J Row 13: L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K Calculation needed: This table is used for Vigenere cipher encryption/decryption by finding the intersection of a plaintext letter (row) and a key letter (column) to get the ciphertext letter. Context: Illustrates the Vigenere cipher mechanism for encrypting a letter by shifting it based on a key letter, specifically showing a shift of 24 positions. **TABLE**: Vigenere Cipher Table (Shift 10) Description: A 26x26 Vigenere cipher table showing the English alphabet. The first row and column are the standard alphabet A-Z. Each subsequent row is a Caesar cipher shift of the previous row. In this specific example, the letter 'K' (from the plaintext/row) is highlighted in orange, and the letter 'K' (from the key/column) is highlighted in green. Their intersection, the letter 'V', is highlighted in red, indicating the result of a 10-position shift. Table Structure: Headers: 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 Rows: Row 1: 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 Row 2: 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 | A Row 3: 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 | A | B Row 4: C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C Row 5: D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D Row 6: E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E Row 7: F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F Row 8: G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G Row 9: H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H Row 10: I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I Row 11: J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J Row 12: K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K Calculation needed: This table is used for Vigenere cipher encryption/decryption by finding the intersection of a plaintext letter (row) and a key letter (column) to get the ciphertext letter. Context: Illustrates the Vigenere cipher mechanism for encrypting a letter by shifting it based on a key letter, specifically showing a shift of 10 positions. **TABLE**: Vigenere Cipher Table (Shift 4) Description: A 26x26 Vigenere cipher table showing the English alphabet. The first row and column are the standard alphabet A-Z. Each subsequent row is a Caesar cipher shift of the previous row. In this specific example, the letter 'O' (from the plaintext/row) is highlighted in orange, and the letter 'E' (from the key/column) is highlighted in green. Their intersection, the letter 'S', is highlighted in red, indicating the result of a 4-position shift. Table Structure: Headers: 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 Rows: Row 1: 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 Row 2: 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 | A Row 3: 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 | A | B Row 4: C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C Row 5: D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D Row 6: E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E Row 7: F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F Row 8: G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G Row 9: H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H Row 10: I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I Row 11: J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J Row 12: K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K Row 13: L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K Row 14: M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K | L Row 15: N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K | L | M Row 16: O | P | Q | R | S | T | U | V | W | X | Y | Z | A | B | C | D | E | F | G | H | I | J | K | L | M | N Calculation needed: This table is used for Vigenere cipher encryption/decryption by finding the intersection of a plaintext letter (row) and a key letter (column) to get the ciphertext letter. Context: Illustrates the Vigenere cipher mechanism for encrypting a letter by shifting it based on a key letter, specifically showing a shift of 4 positions.