As was discussed in Chapter 5, the addressing scheme used by the TCP/IP protocol stack is provided by the IP protocol. As you already know (if you read Chapter 5), the IP addressing scheme has been divided into three classes: A, B, and C. Each of these classes has a default subnet mask.
For devices to communicate on the network, they must be configured with a valid IP address and subnet mask. One way to configure a computer or network printer with an IP address and subnet mask is to manually configure the device. We will look at configuring a PC with an IP address and subnet mask in a moment.
For a computer (or other device) to communicate properly on an IP network, there are also other IP- related parameters that need to be configured on the computer. For example, computers on a network need to be configured with the IP address of the network DNS server (or servers). DNS is used to resolve "friendly names " to IP addresses (and vice versa). DNS is discussed later in the chapter.
Computers also need to be configured with a default gateway. The default gateway is the router for the segment of the network that the computers belong to. Each segment connects to a router interface that has its own IP address (just like a network interface cardrouting is discussed later in the chapter).
If you are still using legacy versions of the Windows operating system on client computers (pre-Windows 2000 versions) on a Microsoft Windows network, the computers (and some legacy applications) rely on NetBIOS names to communicate. On an IP network, there must be a mechanism that resolves NetBIOS names to IP addresses. A server running the Windows Internet Naming Service (WINS) can resolve NetBIOS names to IP addresses. If you use WINS on the network, it makes sense to configure the IP settings of your clients so that they know the IP address of the WINS server.
So, you can see that there is more to configuring an IP client than just providing a unique IP address and the appropriate subnet mask. Let's take a look at how you configure the various IP related settings discussed in this section. We can then look at an alternative to manually configuring IP clients.