SonicWALL 3 Benutzerhandbuch

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22
Chapter 22: 
Setting Up the WLAN Using the
Wireless Wizard and Monitoring
Your WLAN
The SonicWALL TZ 50 Wireless/TZ 150 Wireless/TZ 70 Wireless support two wireless protocols 
called IEEE 802.11b and 802.11g, commonly known as Wi-Fi, and sends data via radio 
transmissions. The TZ 150 Wireless/TZ 170 Wireless combines three networking components to offer 
a fully secure wireless firewall: an Access Point, a secure wireless gateway, and a stateful firewall 
with flexible NAT and VPN termination and initiation capabilities. With this combination, the TZ 50 
Wireless/TZ 150 Wireless/TZ 170 Wireless offer the flexibility of wireless without compromising 
network security. 
Typically, the TZ 50 Wireless/TZ 150 Wireless/TZ 170 Wireless is the access point for your wireless 
LAN and serves as the central access point for computers on your LAN. In addition, it shares a single 
broadband connection with the computers on your network. Since the TZ 50 Wireless/TZ 150 
Wireless/TZ 170 Wireless also provides firewall protection, intruders from the Internet cannot access 
the computers or files on your network. This is especially important for an “always-on” connection 
such as a DSL or T1 line that is shared by computers on a network.
However, wireless LANs are vulnerable to “eavesdropping” by other wireless networks which means 
you should establish a wireless security policy for your wireless LAN. On the TZ 50 Wireless/TZ 150 
Wireless/TZ 170 Wireless, wireless clients connect to the Access Point layer of the firewall. Instead of 
bridging the connection directly to the wired network, wireless traffic is first passed to the Secure 
Wireless Gateway layer where the client is required to be authenticated via User Level Authentication. 
Access to Wireless Guest Services (WGS) and MAC Filter Lists are managed by the TZ 50 Wireless/
TZ 150 Wireless/TZ 170 Wireless. It is also at this layer that the TZ 50 Wireless/TZ 150 Wireless/TZ 
170 Wireless has the capability of enforcing WiFiSec, an IPSec-based VPN overlay for wireless 
networking. As wireless network traffic successfully passes through these layers, it is then passed to 
the VPN-NAT-Stateful firewall layer where WiFiSec termination, address translation, and access rules 
are applied. If all of the security criteria is met, then wireless network traffic can then pass via one of 
the following Distribution Systems (DS):
LAN
WAN
Wireless Client on the WLAN
VPN tunnel