Chapter 2: Planning Your Wireless Network; Network Topology; Figure 2-1: Infrastructure Network - Linksys WET54G V3 User Manual

Wireless-G Ethernet Bridge

Chapter 2: Planning Your Wireless Network

Network Topology

A wireless local area network (WLAN) is exactly like a regular local area network (LAN), except that each
computer in the WLAN uses a wireless device to connect to the network. Computers in a WLAN share the same
frequency channel and SSID, which is an identification name shared by the wireless devices belonging to the
same wireless network.
Ad-Hoc versus Infrastructure Mode
Unlike wired networks, wireless networks have two different modes in which they may be set up: infrastructure
and ad-hoc. An infrastructure configuration is a WLAN and wired LAN communicating to each other through an
access point. An ad-hoc configuration is wireless-equipped computers communicating directly with each other.
Choosing between these two modes depends on whether or not the wireless network needs to share data or
peripherals with a wired network or not.
If the computers on the wireless network need to be accessible by a wired network or need to share a peripheral,
such as a printer, with the wired network computers, the wireless network should be set up in Infrastructure
mode. The basis of Infrastructure mode centers around an access point, which serves as the main point of
communications in a wireless network (see Figure 2-1). Access points transmit data to PCs equipped with
wireless network cards, which can roam within a certain radial range of the access point. Multiple access points
can be arranged to work in succession to extend the roaming range, and can be set up to communicate with your
Ethernet hardware as well.
If the wireless network is relatively small and needs to share resources only with the other computers on the
wireless network, then the Ad-Hoc mode can be used. Ad-Hoc mode allows computers equipped with wireless
transmitters and receivers to communicate directly with each other, eliminating the need for an access point. The
drawback of this mode is that in Ad-Hoc mode, wireless-equipped computers are not able to communicate with
computers on a wired network. And, of course, communication between the wireless-equipped computers is
limited by the distance and interference directly between them.
Figure 2-2 shows a typical scenario of four Wireless-G Ethernet Bridges in ad-hoc mode. Figure 2-3 shows a
typical wireless bridging scenario using two Wireless-G Ethernet Bridges. Each wireless network is connected to
a Wireless-G Ethernet Bridge through a switch. A separate notebook computer is equipped with a wireless
network adapter and can communicate with either wireless network when it is configured with the appropriate
SSID and channel.
Chapter 2: Planning Your Wireless Network
Network Topology
LAN (Local Area Network): the
computers and networking products
that make up your local network.
SSID: your wireless network's name.
Infrastructure: a wireless network
that is bridged to a wired network via
an access point.

Figure 2-1: Infrastructure Network

Ad-hoc: a group of wireless devices
communicating directly to each other
(peer-to-peer) without the use of an
access point.
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