Netgear FVM318 – Cable and DSL ProSafe Wireless VPN Security Firewall Manual De Referencia

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Reference Manual for the Model FVM318 Cable/DSL ProSafe Wireless VPN Security Firewall
Network, Routing, Firewall, and Wireless Basics
B-13
 
In the infrastructure mode, the wireless access point converts airwave data into wired Ethernet 
data, acting as a bridge between the wired LAN and wireless clients. Connecting multiple Access 
Points via a wired Ethernet backbone can further extend the wireless network coverage. As a 
mobile computing device moves out of the range of one access point, it moves into the range of 
another. As a result, wireless clients can freely roam from one Access Point domain to another and 
still maintain seamless network connection.
Extended Service Set Identification (ESSID)
The Extended Service Set Identification (ESSID) is one of two types of Service Set Identification 
(SSID). In an ad hoc wireless network with no access points, the Basic Service Set Identification 
(BSSID) is used. In an infrastructure wireless network that includes an access point, the ESSID is 
used, but may still be referred to as SSID.
An SSID is a thirty-two character (maximum) alphanumeric key identifying the name of the 
wireless local area network. Some vendors refer to the SSID as network name. For the wireless 
devices in a network to communicate with each other, all devices must be configured with the 
same SSID.
Authentication and WEP Encryption
The absence of a physical connection between nodes makes the wireless links vulnerable to 
eavesdropping and information theft. To provide a certain level of security, the IEEE 802.11 
standard has defined two types of authentication methods, Open System and Shared Key. With 
Open System authentication, a wireless PC can join any network and receive any messages that are 
not encrypted. With Shared Key authentication, only those PCs that possess the correct 
authentication key can join the network. By default, IEEE 802.11 wireless devices operate in an 
Open System network. 
Wired Equivalent Privacy (WEP) data encryption is used when the wireless devices are configured 
to operate in Shared Key authentication mode. There are two shared key methods implemented in 
most commercially available products, 64-bit and 128-bit WEP data encryption.
802.11b Authentication
The 802.11b standard defines several services that govern how two 802.11b devices communicate. 
The following events must occur before an 802.11b Station can communicate with an Ethernet 
network through an access point such as the one built in to the FVM318:
1.
Turn on the wireless station.