Consider the following definitions within the context of an asymmetric cryptosystem:
Alice is the owner of a pair of asymmetric cryptographic keys
PUBA - her public key
PRIVA - her private key
Bob is the owner of a pair of asymmetric cryptographic keys
PUBB - his public key
PRIVB - his private key
Encrypting a message can be represented withe the following:
A -> B: M
Alice sends Bob message M
C is a ciphertext
M is a message
K is a key
E( ) is an encryption algorithm
D( ) is a decryption algorithm
H( ) is a hashing algorithm
C = E(M, K1)
You get the ciphertext by encrypting the message with Key K1
M = D(C, K2)
You get the message by decrypting the message with Key K2
h = H(M)
You get the hash of message M
Use the above definitions to show how to provide security to communications between Alice and Bob. Below is an example:
Alice encrypts a message with her public key and sends it to Bob:
A -> B: E(M, PUBA)
QUESTIONS
Show how Alice can send a message to Bob that preservers ONLY the confidentiality of the message.
Show how Bob can send a message to Alice that enables Alice to verify the integrity of the message.
Show how Alice can send a message to Bob that preserves the message's confidentiality while also providing Bob the ability to verify the message's integrity.
Show how Bob can send a signed message to Alice that includes his digital signature.