Chapter 8: Network Access and Security

Overview

THE FOLLOWING NETWORK+ EXAM OBJECTIVES ARE COVERED IN THIS CHAPTER:

• 2.13 Identify the following security protocols and describe their purpose and function:

  • IPSec

  • L2TP

  • SSL

  • Kerberos

• 3.8 Identify the purpose, benefits, and characteristics of using a firewall.

• 3.9 Identify the purpose, benefits, and characteristics of using a proxy.

• 3.10 Given a scenario, predict the impact of a particular security implementation on network functionality (e.g., blocking port numbers, encryption, etc.).

There are two prerequisites that you should keep in mind when you access a resource on the network: network access and the proper security clearance. These items work together to allow you access to a particular resource.

The first of these two topics that you need to consider is network access. Network access involves installing client software on your computer. This software gives your computer the instructions that it needs to be able to access the network.

Network security involves ensuring that only authorized users have access to the network and that they access it only in authorized ways. You want to ensure that hardware, software, and data are available to authorized users when they are needed, but you also want to ensure that hardware, software, and data are not compromised or threatened. In addition to providing network access, client software works with the network operating system to provide network security.

As a network administrator, you can create an effective security plan in a number of ways and by using a variety of tools and procedures. Some of these are practical, commonsense safeguards, and others involve implementing protective systems and technologies. Although numerous recent examples indicate that almost no network is completely immune to security breaches, taking advantage of the measures in this chapter gives you a head start.

You’ll start by learning the different types of clients and how they are installed. You’ll then learn some of the simplest of security measures, usernames, and passwords, including good and bad examples. You’ll then move on to the more complex ways to secure your network—firewalls and proxies. Finally, you’ll learn about some threats that may exist for your network. The Network+ exam covers all of these topics.

Tip 

One aspect we don’t discuss in this chapter is physical security, which the Network+ exam doesn’t include. But remember: If someone can walk in and take your server or backup tapes, you don’t have much security at all. In the real world, you’ll want to ensure that all appropriate and necessary physical mechanisms are in place to protect your network.