Exercise 7.5 Write a simple authentication mechanism (without using encrypted transfer of...

Exercise 7.5 Write a simple authentication mechanism (without using encrypted transfer of passwords, for simplicity). We say a user is authenticated if she has provided a valid username-password combination to the system; otherwise, we say the user is not authenticated. Assume for simplicity that you have a database schema that stores only a customer id and a password:

Passwords(cid: integer, username: string, password: string)

1. How and where are you going to track when a user is ‘logged on’ to the system?
2. Design a page that allows a registered user to log on to the system.
3. Design a page header that checks whether the user visiting this page is logged in.