Alice wants to send Bob a very large message m. The confidentiality and integrity of the message should be protected. Design two separate communication protocols as follows:

1. Design a communication protocol that protects the message's confidentiality and integrity. Describe the message format in detail. Assume that, before the communication happens, Alice and Bob know each other's public key.

2. Design a communication protocol that protects the message's confidentiality and integrity. Describe the message format in detail. Assume that, before the communication happens, Alice and Bob already share a secret key k.