To achieve true seamless connectivity, the wireless LAN must incorporate a
number of different functions. Each node and Wireless AP + Cable/DSL
Router, for example, must always acknowledge receipt of each message. Each
node must maintain contact with the wireless network even when not actually
transmitting data. Achieving these functions simultaneously requires a dynam-
ic RF networking technology that links Wireless AP + Cable/DSL Routers and
nodes. In such a system, the user’s end node undertakes a search for the best
possible access to the system. First, it evaluates such factors as signal strength
and quality, as well as the message load currently being carried by each
Wireless AP + Cable/DSL Router and the distance of each Wireless AP +
Cable/DSL Router to the wired backbone. Based on that information, the node
next selects the right Wireless AP + Cable/DSL Router and registers its address.
Communications between end node and host computer can then be transmitted
up and down the backbone.
As the user moves on, the end nodes RF transmitter regularly checks the sys-
tem to determine whether it is in touch with the original Wireless AP +
Cable/DSL Router or whether it should seek a new one. When a node no longer
receives acknowledgment from its original Wireless AP + Cable/DSL Router,
it undertakes a new search. Upon finding a new Wireless AP + Cable/DSL
Router, it then re-registers, and the communication process continues.
What is BSS ID? A specific Ad hoc LAN is called a Basic Service Set (BSS).
Computers in a BSS must be configured with the same BSS ID.
What is ESS ID? An Infrastructure configuration could also support roaming
capability for mobile workers. More than one BSS can be configured as an
Extended Service Set (ESS). Users within an ESS could roam freely between
BSSs while served as a continuous connection to the network wireless stations
and Wireless AP + Cable/DSL Routers within an ESS must be configured with
the same ESS ID and the same radio channel.
What is ISM band? The FCC and their counterparts outside of the U.S. have set
aside bandwidth for unlicensed use in the ISM (Industrial, Scientific and
Medical) band. Spectrum in the vicinity of 2.4 GHz, in particular, is being
made available worldwide. This presents a truly revolutionary opportunity to
place convenient high-speed wireless capabilities in the hands of users around
the globe.
What is Spread Spectrum? Spread Spectrum technology is a wideband radio
frequency technique developed by the military for use in reliable, secure, mis-
sion-critical communications systems. It is designed to trade off bandwidth
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How do I get mIRC to work with the Wireless AP + Cable/DSL Router? Set port for-
warding to 113 for the computer on which you are using mIRC.
Can I run an application from a remote computer over the wireless network? This
will depend on whether or not the application is designed to be used over a net-
work. Consult the application's user guide to determine if it supports operation
over a network.
Can I play computer games with other members of the cordless network? Yes, as
long as the game supports multiple players over a LAN (local area network).
Refer to the game's user guide for more information.
What is the IEEE 802.11b standard? The IEEE 802.11b Wireless LAN standards
subcommittee, which is formulating a standard for the industry. The objective
is to enable wireless LAN hardware from different manufacturers to communi-
cate.
What IEEE 802.11 features are supported? The Wireless AP + Cable/DSL Router
supports the following IEEE 802.11 functions:
• CSMA/CA plus Acknowledge protocol
• Multi-Channel Roaming
• Automatic Rate Selection
• RTS/CTS feature
• Fragmentation
• Power Management
What is Ad-hoc? An Ad-hoc wireless LAN is a group of computers, each with
a WLAN adapter, connected as an independent wireless LAN. Ad-hoc wireless
LAN is applicable at a departmental scale for a branch or SOHO operation.
What is Infrastructure? An integrated wireless and wired LAN is called an
Infrastructure configuration. Infrastructure is applicable to enterprise scale for
wireless access to central database, or wireless application for mobile workers.
What is Roaming? Roaming is the ability of a portable computer user to com-
municate continuously while moving freely throughout an area greater than that
covered by a single Wireless Network Access Point. Before using the roaming
function, the PC must make sure that it is the same channel number with the
Wireless AP + Cable/DSL Router of dedicated coverage area.
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Etherfast
®
Wireless AP + Cable/DSL Router with PrintServerInstant Broadband
TM
Series