CNP-WF511N2
Wireless N PCI Adapter
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developed by the military for use in reliable, secure, mission-critical communications systems.
It is designed to trade off bandwidth efficiency for reliability, integrity, and security. In other
words, more bandwidth is consumed than in the case of narrowband transmission, but the
trade off produces a signal that is, in effect, louder and thus easier to detect, provided that the
receiver knows the parameters of the spread-spectrum signal being broadcast. If a receiver is
not 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).
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SSID -
A
S
ervice
S
et
Id
entification is a thirty-two character (maximum) alphanumeric key
identifying a wireless local area network. For the wireless devices in a network to
communicate with each other, all devices must be configured with the same SSID. This is
typically the configuration parameter for a wireless PC card. It corresponds to the ESSID in
the wireless Access Point and to the wireless network name.
See also
Wireless Network
Name and ESSID.
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WEP -
(
W
ired
E
quivalent
P
rivacy)
-
A data privacy mechanism based on a 64-bit or 128-bit or
152-bit shared key algorithm, as described in the IEEE 802.11 standard. To gain access to a
WEP network, you must know the key. The key is a string of characters that you create.
When using WEP, you must determine the level of encryption. The type of encryption
determines the key length. 128-bit encryption requires a longer key than 64-bit encryption.
Keys are defined by entering in a string in HEX (hexadecimal - using characters 0-9, A-F) or
ASCII (American Standard Code for Information Interchange – alphanumeric characters)
format. ASCII format is provided so you can enter a string that is easier to remember. The
ASCII string is converted to HEX for use over the network. Four keys can be defined so that
you can change keys easily.
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Wi-Fi -
A trade name for the 802.11b wireless networking standard, given by the Wireless
Ethernet Compatibility Alliance (WECA, see http://www.wi-fi.net), an industry standards
group promoting interoperability among 802.11b devices.
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WLAN -
(
W
ireless
L
ocal
A
rea
N
etwork) - A group of computers and associated devices
communicate with each other wirelessly, which network serving users are limited in a local
area.
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WPA -
(
W
i-Fi
P
rotected
A
ccess)
-
A wireless security protocol uses TKIP (Temporal Key
Integrity Protocol) encryption, which can be used in conjunction with a RADIUS server.