Networking Basics

In today's society, it is important to both know the ins and outs of your computer and to understand in greater detail how your computer interfaces with networks. As was discussed in Chapter 1, networks play an integral roll in computer communication. There are specific details that will allow you to be a stronger computer user. Understanding how your computer connects to a network is only the first step in appreciating the complexity and power of networks. Networks allow for the sharing of informaiton among devices along many different mediums as well as over great distances. There are many ways for networks to be setup and established involving various mediums, hardware, and network layout.

Establishing a Network Connection

When you connect to a network, whether via a cable or wirelessly, several things happen to make your network connection successful. First, your computer must obtain an IP Address.  An IP address is just like a house address; it lets the other computers know where you are located and how to send you information.  This address can either be set manually by you the user or, as is most often the case, set dynamically by a controlling device. The device (either a computer or router) that is controlling the addressing for the network uses a technology known as DHCP (Dynamic Host Configuration Protocol) to lease to your computer an address.  This lease is usually for a set amount of time. This method of handing out addresses is used most often because it allows network administrators to control access to their network and allow new computers to enter the network without manually configuring each new machine.

Once your computer has an address, it then makes a request for DNS Server Addresses.  These servers provide you and your computer the ability to use DNS (Domain Name System). DNS allows you to use domain names instead of actual addresses to access a computer. For example, instead of having to type in the actual IP address of the computer that is hosting Google search engine, I can instead type www.google.com into my browser and will be sent to the appropriate computer.  DNS Servers keep track of the domain names and to what IP addresses they should point.

At this point in a regular network you would have network access.  At NC State this is where Nomad (see Nomad) steps in to authenticate you as a valid NC State computing account user.