Modecom MC-105USB, User Manual

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WIRELESS NETWORK USB ADAPTER
still maintaining a networking connection. In essence, WLANs are an extension of wired LAN networks, where
the critical need is data access and mobility. The tradeoff s are slower speeds (although quite satisfactory for
Internet and email access) and limited roaming distance, as dictated by the environment.
A basic WLAN network requires client nodes and access points, similar to a LAN with its clients and infrastructu-
re (switches, repeaters, etc.). The access point is the connection to the wired LAN network or a designated com-
puter device performing the supervisory function, while client nodes are typically WLAN adapters installed
in peripheral computing devices, such as notebooks, desktops, personal digital assistants (PDAs) and others.
Once a WLAN is setup, it acts like a wired LAN, using the same protocols designated for communicating via the
IEEE Ethernet standard.
2.1 Wireless LAN Network Modes
WLANs basically have two modes of operation:
• Ad-Hoc mode
• Infrastructure mode
Ad-Hoc Mode
An Ad-Hoc WLAN is created when two or more PCs equipped with Wireless LAN Cards (WLAN clients) are con-
fi gured to use the same radio channel and Network Name in the same area and can communicate freely with
each other, without the need for an Access Point to a hard-wired LAN network. Only PCs that use the same ra-
dio channel and network name can communicate over the Ad-Hoc network. This type of a network is a peer-to-
peer relationship where each computer talks directly to one another with no one PC being dominant.
Figure 2 Ad-Hoc Mode: Two or More PCs with 802.11b/g Wireless LAN Cards Confi gured to Same Radio
Channel and Network Name