Campbell NL241, Инструкция по эксплуатации

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NL241 Wireless Network Link Interface
13
Contains an embedded radio transmitter with the following approvals:
FCC Identifier: XF6-RS9113SB
Industry Canada: 8407A-RS9113SB
View the EU Declaration of Conformity at www.campbellsci.com/nl241
6. Wi-Fi
6.1 Introduction to Wi-Fi for WLANs
Wi-Fi is a technology that allows data transfer among electronic devices using
specific radio frequencies over a wireless local area network (WLAN). A
wireless network is like a wired network, except it uses radio waves just like
cell phones, televisions, and other radios. Over-the-air speeds vary depending
on protocol, distance, and network activity. When using the NL241, please
note that your total throughput to the datalogger will generally be governed by
the speed of serial communication.
Wi-Fi transmits at frequencies around 2.4 and 5 GHz (the NL241 only uses 2.4
GHz). The high frequency allows fast rates but reduced communication
distance. These frequencies can be used by anyone and do not require a license
from the FCC to use or transmit (unlike most UHF and VHF frequencies) as
long as certain power levels are maintained.
The NL241 supports the 802.11b, 802.11g, and 802.11n wireless network
standards.
The NL241 also supports several wireless security protocols. These include
WEP (Wired Equivalent Privacy), WPA (Wi-Fi Protected Access) (personal),
WPA2 (Wi-Fi Protected Access II) (personal), and WPA/WPA2-Enterprise.
These security protocols allow network traffic to be encrypted and help protect
data transmitted over the Wi-Fi network.
6.2 Wireless Network Modes
Join a Network:
The NL241 can be configured to join an already established infrastructure
wireless network (WLAN) (see FIGURE 6-1 ). An infrastructure wireless
network is one in which all devices or stations (STA) communicate through an
access point (AP). This AP will typically connect the wireless network (and the
NL241) to a larger wired company or home network and/or the internet. The
AP device also controls and routes all the traffic on the wireless network. Once
the NL241 has successfully joined the existing wireless network, it can
communicate with other devices on the network.
The AP, furthermore, controls security for network access, the wireless
frequency (channel) to use, and has the pre-established Service Set Identifier
(SSID) for the wireless network. The SSID (or network name) and
password/key (if required) can be obtained from your network administrator.