User's Manual

Netkey Series WLAN Card
WWW.TwinMOS.COM
Page 4
3 WIRELESS NETWORK OVERVIEW
A wireless local area network (LAN) is a flexible data communications system implemented as an
extension to, or as an alternative for, a wired LAN. Using radio frequency (RF) technology, wireless
LANs transmit and receive data over the air, minimizing the need for wired connections. Thus, wireless
LANs combine data connectivity with user mobility.
A local area network that transmit and receive over the air typically in an unlicensed frequency such as
the 2.4GHz band. A wireless LAN does not require lining up devices for line of sight transmission like
IrDA. Wireless access points (base stations) are connected to an Ethernet hub or server and transmit a
radio frequency over an area of several hundred to a thousand feet which can penetrate walls and other
nonmetal barriers. Roaming users can be handed off from one access point to another like a cellular
phone system. Laptops use wireless modems that plug into an existing Ethernet port or that are self
contained on PC cards, while stand-alone desktops and servers use plug-in cards (ISA, PCI, etc.).
Wireless LANs offer the following productivity, convenience, and cost advantages over traditional wired
networks：
Mobility
WLAN provide LAN users to access data in any location within the operating range of the WLAN.
Ad-hoc management decisions based on real-time information can significantly improve worker
efficiency.
Installation Speed and Simplicity
Installing a wireless LAN system can be fast and easy and can eliminate the need to pull cable through
walls and ceilings.
Installation Flexibility
Wireless technology allows the network to go where wire cannot go.
Reduced Cost-of-Ownership
While the initial investme nt required for wireless LAN hardware can be higher than the cost of wired
LAN hardware, overall installation expenses and life-cycle costs can be significantly lower. Long-term
cost benefits are greatest in dynamic environments requiring frequent moves and changes.
Scalability
Wireless LAN systems can be configured in a variety of topologies to meet the needs of specific
applications and installations. Configurations are easily changed and range from peer-to-peer networks
suitable for a small number of users to full infrastructure networks of thousands of users that enable
roaming over a broad area.