Canon 802.11g 54M WLAN - Manual (Page 67)

802.11g 4-Port Wireless LAN Broadband Router
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configuration. Infrastructure is applicable to enterprise scale for wireless access to central
database, or wireless application for mobile workers.
LAN (Local Area Network)
Local Area Networking (LAN) is the term used when connecting several computers
together over a small area such as a building or group of buildings. LAN’s can be
connected over large areas. A collection of LAN’s connected over a large area is called a
Wide Area Network (WAN). A LAN consists of multiple computers connected to each other.
There are many types of media that can connect computers together. The most common
media is CAT.5 cable (UTP or STP twisted pair wire.) On the other hand, wireless networks
do not use wires; instead they communicate over radio waves. Each computer must have a
Network Interface Card (NIC), which communicates the data between computers. A NIC is
usually a 10Mbps network card, or 10/100Mbps network card, or a wireless network card.
Most networks use hardware devices such as hubs or switches that each cable can be
connected to in order to continue the connection between computers. A hub
simply takes any data arriving through each port and forwards the data to all other ports. A
switch is more sophisticated, in that a switch can determine the destination port for a
specific piece of data. A switch minimizes network traffic overhead and speeds up the
communication over a network.
NAT (Network Address Translation)
For a computer to communicate with other computers on the Internet, it must have an IP
address. An IP (Internet Protocol) address is a unique 32-bit number that identifies the
location of your computer on a network. However, with the explosion of the Internet, the
number of available IP addresses is simply not enough.
This is where NAT comes to the rescue. Network Address Translation allows a single
device, such as a router, to act as an agent between the Internet (or “public network”) and a
local (or “private”) network. This means that only a single, unique IP address is required to
represent an entire group of computers.
Roaming
The ability to use a wireless device is able to move from one access point range to another
without losing the connection.
RTS/CTS Threshold Value
It should remain at its default setting of 2,347. A preamble is a signal used to synchronize
the transmission timing between two or more systems. A series of transmission pulses is
sent before the data to indicate that someone is about transmit data. This ensures that
systems receiving the information correctly when the data transmission starts.