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Chapter 1

Planning a Network Topology

nication protocols common to all network operating systems, the Microsoft Windows

Server 2003 family also includes a collection of applications and services that imple-

ment important security and special communications capabilities on the network.

The significance of the network infrastructure does not end when the construction of

the network is complete, however. The personnel responsible for maintaining the net-

work must have an intimate knowledge of the network’s infrastructure to expand the

network, perform upgrades, and troubleshoot problems. The 70-293 exam tests your

knowledge of how the infrastructure affects the planning, implementation, and main-

tenance of a medium-to-large network, and of how Windows Server 2003 functions as

a part of that infrastructure.

Physical Infrastructure

A network’s physical infrastructure is its topology—the physical design of the net-

work—along with hardware components such as cabling, routers, switches, hubs, serv-

ers, and workstations. The hardware you select when planning the network’s physical

infrastructure is frequently dependent on elements of the network’s logical infrastruc-

ture. For example, if you decide to use Ethernet for your network’s data-link layer pro-

tocol, you are limited to certain specific cable types supported by Ethernet, and the

network’s connectivity components—hubs, routers, and switches—must be designed

for use with Ethernet as well.

For a small network, the physical infrastructure can be very simple—computers, a hub,

and a few cables are generally all you need. For medium-to-large networks, however,

the physical infrastructure can be extraordinarily complex. In addition to a large fleet of

computers, a vast system of cables, and multiple interconnected hubs, the network

might require routers or switches to connect segments, plus the additional components

needed to support Internet connections, remote client access, wide area connections to

other sites, or wireless connectivity.

The hardware used to implement these additional technologies is various and always

relates to the network’s logical infrastructure. For example, to connect the Ethernet

local area network (LAN) in the company headquarters to the Ethernet LAN in a branch

office, you must choose a different data-link layer protocol for the wide area network

(WAN) connection (such as Point-to-Point Protocol), as well as a different network

medium (such as a dial-up or a T-1 connection), and you must be sure that the hard-

ware and software on both LANs support the WAN technology you choose.

See Also For more information on WAN connections, see Lesson 1 in Chapter 3, “Planning

Internet Connectivity,” and Lesson 1 in Chapter 5, “Using Routing and Remote Access.”