In a public key, cryptosystem using RSA algorithm, user uses two prime numbers 5 and 7. He chooses 11 as Encryption key, find out decryption key. What will be the cipher text, if the plaintext is 2? Decrypt the cipher text, what will be the value of plain text?

Apply Vernam Cipher for both the encryption and decryption process. Plaintext = "forty four love" , Key = "do programming" How double transposition cipher works?

On Groundhog Day, the groundhog randomly chooses and sends one of two possible messages: m0 = SIXMOREWEEKSOFWINTER m1 = SPRINGARRIVESINMARCH. To add to the mystery, the groundhog encrypts the message using one of the following methods: shift cipher, Vigenère cipher with key length 4 (using four distinct shifts), one-time pad. For each of the following ciphertexts, determine which encryption methods could have produced that ciphertext, and for each of these possible encryption methods, decrypt the message or explain why it is impossible to decrypt. a. ABCDEFGHIJKLMNOPQRST b. UKZOQTGYGGMUQHYKPVGT c. UQUMPHDVTJYIUJQQCSFL.

I need help with the following problems in cryptography. A. Encrypt the message “Freedom” using the Playfair matrix M F H I K U N O P Q Z V W X Y E L A R G D S T B C T B. Construct the Playfair matrix with the keyword “LARGEST” and encrypt the message “Freedom” again. C. Compare the results obtained in A and B. How do you account for these results?

One of the one-way functions used in public key cryptography is integer multiplication/factorization. Multiplying two integers is easy, but factoring is hard. The number 1765243 is the product of two primes. What is the smaller of the two primes? What is the largest of the two primes?

Perform encryption and decryption using the RSA algorithm for the letter "S". Show all steps in details when p=5 , q=7 , e=5.

Alice sets up an RSA public/private key, but instead of using two primes, she chooses three primes p, q, and r and she uses n=pqr as her RSA-style modulus. She chooses an encryption exponent e and calculates a decryption exponent d. Encryption and Decryption are defined: C ≡ me mod n and m ≡ Cd mod n where C is the ciphertext corresponding to the message m.  Decryption: de ≡ 1 mod φ(n) | Let p = 5, q = 7, r = 3, e = 11, and the decryption exponent d = -13. n = 105 & φ(n) = 48 Q: Alice upgrades to three primes that are each 200 digits long. How many digits does n have?

Bob's El Gamal prime number is p=907 and his secret key is a=16. Alice has encrypted x=13 for sending to Bob and her ciphertext is (37,♦). What is ♦ (mod p)? Select one: a. 512 b. 418 c. 253 d. 96 e. 419

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Decode the number using the given private key. Decode the number M = 15 using the private key d = 53 and n = 77. Assume you are decoding the number using the RSA cryptosystem. Note: You can use the Modular Exponentiation calculator to help with the calculation. a 63 (mod 77), decoded number = 63 b 64 (mod 77), decoded number = 64 C 65 (mod 77), decoded number = 65 d. 66 (mod 77), decoded number = 66