Networking: A Beginner's Guide
ne of the strengths of Windows Server 2008 is that it can perform many
functions and fill many roles. Not only is Windows Server 2008 a powerful
and effective file server and print server, but it's also extremely capable of
performing many other tasks right out of the box.
Chapters 16 and 17 explained how to set up Windows Server 2008 as a basic file
server and print server, and how to administer Windows Server 2008 on a daily basis.
To get the most out of Windows Server 2008, you need to know what additional services
are available, how they work, and what they do. This chapter introduces some of the
other services that come with Windows Server 2008. You can find detailed instructions
for implementing these services in a book devoted to Windows Server 2008.
If you've been involved with computers for long, you probably remember what it was
like to manage TCP/IP addresses manually (and you might still do this now!). You
needed to visit every computer on the network to set its TCP/IP address manually.
You also had to keep track of which computers used which addresses, because you
had a limited number of addresses with which to work. Plus, as you probably know,
when two computers on a network try to use the same TCP/IP address, trouble quickly
follows, and you must spend time sorting out these problems.
As discussed in Chapter 8, the Dynamic Host Configuration Protocol (DHCP) saves
the day in such situations. A DHCP server is a computer on the network that keeps
track of which TCP/IP addresses are available, and parcels them out to computers and
other devices that boot up and request a TCP/IP address from the server. With a DHCP
server, you don't need to worry about address conflicts or renumbering the addresses
used on computers if your TCP/IP address range ever changes.
Because TCP/IP is the default protocol for Windows Server 2008-based networks and
because Windows Server 2008 is designed to operate correctly over a TCP/IP-only network, DHCP
services are installed with Windows Server 2008 by default. However, the DHCP services are not
enabled by default, because you should not set up conflicting DHCP servers on a network.
To use DHCP, you must define a scope and other associated TCP/IP settings that
the servers give to client computers. A scope is simply the range (or ranges) of TCP/IP
addresses that the server is allowed to parcel out.
Among the associated TCP/IP settings that the server distributes are the addresses
for Domain Name System (DNS) or Windows Internet Naming Service (WINS) servers
also on the network. When a DHCP server assigns a TCP/IP address to a client computer,
the address is said to be leased, and it remains assigned to that client computer for a set
period of time. Leases are usually configured to last for two to seven days. (The default
setting in Windows Server 2008 is eight days.) During this period, the assigned TCP/IP
address is not given out to a different computer.