Linksys WRT54AG User Manual page 44

tuned to the right frequency, a spread-spectrum signal looks like background
noise. There are two main alternatives, Direct Sequence Spread Spectrum
(DSSS) and Frequency Hopping Spread Spectrum (FHSS).
What is DSSS? What is FHSS? And what are their differences?
Frequency-Hopping Spread-Spectrum (FHSS) uses a narrowband carrier that
changes frequency in a pattern that is known to both transmitter and receiver.
Properly synchronized, the net effect is to maintain a single logical channel. To
an unintended receiver, FHSS appears to be short-duration impulse noise.
Direct-Sequence Spread-Spectrum (DSSS) generates a redundant bit pattern
for each bit to be transmitted. This bit pattern is called a chip (or chipping
code). The longer the chip, the greater the probability that the original data can
be recovered. Even if one or more bits in the chip are damaged during trans-
mission, statistical techniques embedded in the radio can recover the original
data without the need for retransmission. To an unintended receiver, DSSS
appears as low power wideband noise and is rejected (ignored) by most nar-
rowband receivers.
Will the information be intercepted while it is being transmitted through the air?
WLAN features two-fold protection in security. On the hardware side, as with
Direct Sequence Spread Spectrum technology, it has the inherent security fea-
ture of scrambling. On the software side, WLAN offers the encryption function
(WEP) to enhance security and access control.
What is WEP?
WEP is Wired Equivalent Privacy, a data privacy mechanism based on a 64-bit
or 128-bit shared key algorithm, as described in the IEEE 802.11 standard.
What is a MAC Address?
The Media Access Control (MAC) address is a unique number assigned by the
manufacturer to any Ethernet networking device, such as a network adapter,
that allows the network to identify it at the hardware level. For all practical pur-
poses, this number is usually permanent. Unlike IP addresses, which can
change every time a computer logs onto the network, the MAC address of a
device stays the same, making it a valuable identifier for the network.
How do I avoid interference?
If you are using the Router and one or more Access Points in close proximity
to one another, and they are set on the same channel, interference will be gen-
erated. To avoid interference, be sure to set the Router and all Access Points to
different channels (frequencies); in other words, assign a unique channel to the
Router and each Access Point.
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Dual-Band Wireless A/G Broadband Router
How do I reset the Router?
Press the Reset button on the back panel for about ten seconds. This will reset
the Router to its default settings.
How do I resolve issues with signal loss?
There is no way to know the exact range of your wireless network without test-
ing. Every obstacle placed between the Router and a wireless PC will create
signal loss. Lead glass, metal, concrete floors, water and walls will inhibit the
signal and reduce range. Start with the Router and your wireless PC in the
same room and move it away in small increments to determine the maximum
range in your environment.
You may also try using different channels, as this may eliminate interference
affecting only one channel.
I have excellent signal strength, but I cannot see my network.
WEP is probably enabled on the Router, but not on your wireless adapter (or
vice versa). Verify that the same WEP keys and levels (64 or 128) are being
used on all nodes of your wireless network.
How many channels/frequencies are available with the Router?
There are eleven available channels, ranging from 1 to 11 (in North America).
If your questions are not addressed here, refer to the Linksys website,
www.linksys.com.
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