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2. Planning Your Wireless Network
2.1 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 for wireless devices.
2.2 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 accessed 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. (See Figure 2-1.) The
basis of infrastructure mode centers around an
access point
, which serves as the main
point of communications in a wireless network. 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
(wired) hardware as well.
Figure 2-1
If the wireless network is relatively small and needs to share resources only with the
