Problem
1. You want to write a song and apply a digital signature to it, so that you can later prove that it is your song. How do you apply the signature; and later on, how would you use it to prove that the song is yours?
2. List three examples (other than those listed in the chapter) of everyday actions that might benefit from applying PKI.
3. Can a firewall filter out requests to a particular IP address, a port address, or both? What is the difference?