UNIT3-PUBLIC KEY CRYPTOGRAPHY

One commonly used public-key cryptography method is the ______ algorithm.

• RSA

• AES

• DES

• Both AES & DES

The ________ method provides a one-time session key for two parties.

• Diffie Hellman

• RSA

• AES

• DES

Using Rivest, Shamir, Adleman cryptosystem with p=7 and q=9. Encrypt M=24 to find ciphertext. The Ciphertext is:

• 114

• 42

• 93

• 110

Suppose that two parties A and B wish to setup a common secret key (D-H key) between themselves using the Diffie-Hellman key exchange technique. They agree on 7 as the modulus and 3 as the primitive root. Party A chooses 2 and party B chooses 5 as their respective secrets. Their D-H key is

• 3

• 4

• 5

• 6

One characteristic/drawback of ElGamal Encryption scheme

• Deterministic

• Unconditional security

• Cipher text is double the size of the plain text

• None of the above

What is the hardness assumption behind Schnorr Digital signature scheme?

• Decisional Diffie-Hellman Assumption

• Computational Diffie-Hellman Assumption

• Discrete logarithm

• Factoring Assumption

Which one is not the property of hash functions?

• Efficient

• Easy to invert

• Collision resistant

• Avalanche Effect

Consider the group E_23(9,17) defined by the equation y^2=(x^3+9x+17) mod 23. Given P = (16,5) find 2P

find 3P?

Name the identity element of elliptic curve group