Wireless Access Point Model 0-1591700-x User Manual
Page 6 of 34
©2004 Tyco Electronics
Issue 3
Installation Practice
Wireless LAN systems need a little more planning than conventional wired LANs. This is because
the access point relies on the propagation of radio signals, which are sometimes greatly affected
by a range of factors including:-
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building materials,
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thickness and type of walls,
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proximity of metal,
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proximity of radar and other high power transmitters
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relative positions and characteristics of client devices.
Do I Need A Site Survey ?
If you are uncertain about the characteristics of an intended location for a wireless LAN system,
then it is advisable to obtain a professional site survey. This will provide a report on the current
radio environment and may also make recommendations about the location of access points.
It is possible to conduct your own informal site survey using the software tools provided on some
client WLAN cards. This is achieved by fitting the appropriate client card into the PC,
commissioning and installing the Access Point in the intended position and then moving the PC
around the intended area. Whilst this is not a scientific method, it does provide a quick method of
determining the likely coverage of an area by observing the relative signal strength.
Note that radio environments may change due to new radars, transmitters, access points and
scientific instrumentation being installed near the access point. This means that further site surveys
may be needed in the future to assist in problem diagnosis.
Location Guidelines
a) Ensure that the number of barriers between the access point and client devices are kept to
the absolute minimum. In an ideal environment, there should be “line-of-sight” between the
access point and the client devices.
b) If the access point and clients are separated by walls, then ensure that the wall is relatively
thin and constructed of a material that is of high radio transparency (not steel or re-inforced
concrete etc).
c) If walls separate the client and the access point, then ensure that the wireless devices are
perpendicular to the walls. This reduces the apparent depth of the wall compared with the
signals needing to pass through a wall at an angle.
d) Reduce the distances between the access point and the client devices to maintain high
signal strengths. This will keep the data transfer rates achieved over the wireless links to
the highest possible levels.
e) Consider the availability of power for the access point. If power is not available, then the DC
Power Injector Model 0-15910710-x can be used to inject power for the access point into
the Ethernet cable at the equipment room. This option enables easy remote powering of
distant access points.
WLAN Security
Wireless access points are potentially a security risk to a network if no precautions are taken.
However as with any network, simple precautions can greatly increase the security of a network to
create a highly secure environment. These precautions include:-
1. Change the default SSID setting and password (see pages 21 and 27).
2. Hide the SSID value (see page 23)
3. Implement an 802.1x authentication scheme if at all possible (see page 25).
4. If 802.1x cannot be implemented:-
a. Use the integrated WEP encryption at the highest possible key values and change
the keys on a regular basis (page 24).
b. Use the MAC address based filters (page 20)
5. Place access points on inner walls of a building and use the lowest possible transmit power
settings (see page 22).
