Security notes

What are the security issues?

Confidentiality

Can people see my message?

encryption

How do we establish a secret?

Diffie Hellman algorithm

Authentication

Sending credit card number to Amazon, how can I be sure Amazon is really Amazon?

receiver authentication

How can I trust Amazon's public key?

How can I trust certificate?

Frank sends me a class grade, how can I be sure it is really sent from Frank?

sender authentication

digital signature (reverse the logic)

Password, password

user authentication

How does system store password?

How does password work over the network?

Integrity

Will my message get modified?