Chapter 5 Question 16

13. What is a denial-of-service attack? Why is it so important in e-commerce? Why is it so difficult to prevent?

A DoS can come from many sources, but on the Internet, it is generally created through some type of message flood. Zombie machines and lack of security in underlying Internet protocols make it difficult to prevent. The bottom line is that Internet sites need to accept communication from a huge variety of machines and people, so it is difficult to form rules that would block fake/DoS traffic, but still allow legitimate traffic through.