What is a 3-way handshake? Hint: TCP uses it.

How do TCP/IP networks work?

How does DNS work? Have you ever had DNS go down? When should you have backup DNS – have you ever had to set this up for a website?

How does traceroute work?

You have a MySQL DB, once you login how could you find out the schema of the db? (or any other set of basic SQL commands)