REFACE 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
RIV A - her private key
Bob is the owner of a pair of asymmetric cryptographic keys
PUB8 - his public key
PRIV8 - his private key

Encrypting a message can be represented withe the following:

A-> B: M
Alice sends Bob a 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(m1,k1)
You get the ciphertext by encrypting the message with Key K1
M=D(c1,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 :

1. Show how Alice can send a message to Bob that preservers ONLY the confidentiality of the message.
2. Show how Bob can send a message to Alice that enables Alice to verify the integrity of the message.
3. 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.
4. Show how Bob can send a signed message to Alice that includes his digital signature.