# Email and Key Encryption

P18. Suppose Alice wants to send an e-mail to Bob. Bob has a public-private key pair, and Alice has Bob's certificate. But Alice does not have a public, private key pair. Alice and Bob (and the entire world) share the same hash function.

a. In this situation, is it possible to design a scheme so that Bob can verify that Alice created the message? If so, show how with a block diagram for Alice and Bob.

b. Is it possible to design a scheme that provides confidentiality for sending the message from Alice to Bob? If so, show how with a block diagram for Alice and Bob.

© BrainMass Inc. brainmass.com April 3, 2020, 10:29 pm ad1c9bdddfhttps://brainmass.com/computer-science/hashing/email-key-encryption-444463

#### Solution Preview

The answers to your questions are in the attached Word file.

The answers to your questions are below:

P18. Suppose Alice wants to send an e-mail to Bob. Bob has a public-private key pair, and Alice has Bobâ€™s certificate. But Alice does not have a public, private key pair. Alice ...

#### Solution Summary

This solution discusses email and key encryption. It discusses whether it's possible to design a scheme for verifying a message or confidentiality for sending a message.