This chapter discusses some of the different kinds of services that your router might or might not be running by default, what type of security impact they have, and how to disable them. Many of the services that I discuss here have security issues, each with its own level of risk. A hacker can use these services to his advantage by gathering information about your router, executing a denial of service (DoS) attack, or attempting to gain unauthorized access. Therefore, you need to disable all of the services on your perimeter router (or any router, for that matter) that you are not using or that are unnecessary.
I have divided chapter into three sections:
• How to disable global services
• How to disable ...