Q1. What is the Windows 10 security model based upon?

Q2. The list of all passwords is kept in the operating system. Thus, if a user manages

to read this list, password protection is no longer provided. Suggest a scheme that will

avoid this problem. (Hint: Use different internal and external representations.)

Q3. An experimental addition to UNIX allows a user to connect a watchdog program

to a file. The watchdog is invoked whenever a program requests access to the file. The

watchdog then either grants or denies access to the file. Discuss two pros and two

cons of using watchdogs for security.

Q4. Discuss a means by which managers of systems connected to the Internet could

design their systems to limit or eliminate the damage done by worms. What are thedrawbacks of making the change that you suggest?

Q5. Mobile operating systems such as iOS and Android place the user data and the

system files into two separate partitions. Aside from security, what is an advantage of

that separation?