Security is the most vital part of any network. We must make sure that our information is secure from the outside as well as from the inside. Not only do we have to worry about unauthorized personnel coming in through our WAN connections, we also must be concerned about the employees who are already present inside our network. There could be a potential threat to the company inside as well.
In this chapter, we will cover how to create an Access-Control List that will mitigate threats externally and internally. We will cover standard ACLs, Extended ACLs, Named ACLs, and Remarks. We will briefly cover some aspects of firewalls and their policies.
While going through this chapter, keep in mind that security is done in layers. You need to ask yourself, How vital is the information I am trying to secure, and, How determinedly are people trying to get in?
The following...