Canon 802.11g 54M WLAN - Manual (Page 66)

802.11g 4-Port Wireless LAN Broadband Router
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software or a special piece of hardware built specifically to act as a firewall. In most
circumstances, a firewall is used to prevent unauthorized Internet users from accessing
private networks or corporate LAN’s and Intranets.
A firewall watches all of the information moving to and from your network and analyzes
each piece of data. Each piece of data is checked against a set of criteria that the
administrator configures. If any data does not meet the criteria, that data is blocked and
discarded. If the data meets the criteria, the data is passed through. This method is called
packet filtering.
A firewall can also run specific security functions based on the type of application or type of
port that is being used. For example, a firewall can be configured to work with an FTP or
Telnet server. Or a firewall can be configured to work with specific UDP or TCP ports to
allow certain applications or games to work properly over the Internet.
Firmware
Program that is inserted into programmable read-only memory (programmable read-only
memory), thus becoming a permanent part of a computing device.
Fragmentation Threshold Value
Indicates how much of the network resources are devoted to recovering packet errors. The
value should remain at its default setting of 2,432. If you experience high packet error rates,
you can decrease this value but it will likely decrease overall network performance. Only
minor modifications of this value are recommended.
Fragmentation
Breaking a packet into smaller units when transmitting over a network medium that cannot
support the original size of the packet.
IEEE
The Institute of Electrical and Electronics Engineers
IEEE 802.11b/g standard
The IEEE 802.11b/g Wireless LAN standards subcommittee formulates standards for the
industry. The objective is to enable wireless LAN hardware from different manufacturers to
communicate.
Infrastructure Mode
A client setting provides connectivity to an Access Point. As compared to Ad-Hoc mode
where PCs communicate directly with each other, clients set in Infrastructure mode all pass
data through a central Access Point. The Access Point not only mediates Wireless network
traffic in the immediate neighborhood but also pro-vides communication with the wired
network. An integrated wireless and wireless and wired LAN is called an Infrastructure