3Com 3C17203 - SuperStack 3 Switch 4400, Implementation Manual

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DNS Domain Name System. This system maps a numerical Internet Protocol
(IP) address to a more meaningful and easy-to-remember name. When
you need to access another device on your network, you enter the
name of the device, instead of its IP address.
DUD Disconnect Unauthorized Device. A port security feature that disables a
port if an unauthorized client device transmits data on it.
endstation A computer, printer or server that is connected to a network.
Ethernet A LAN specification developed jointly by Xerox, Intel and Digital
Equipment Corporation. Ethernet networks use CSMA/CD to transmit
packets at a rate of 10 Mbps over a variety of cables.
Ethernet address See MAC address .
Fast Ethernet An Ethernet system that is designed to operate at 100Mbps.
forwarding The process of sending a packet toward its destination using a
networking device.
Forwarding Database See Switch Database .
filtering The process of screening a packet for certain characteristics, such as
source address, destination address, or protocol. Filtering is used to
determine whether traffic is to be forwarded, and can also prevent
unauthorized access to a network or network devices.
flow control A mechanism that prevents packet loss during periods of congestion on
the network. Packet loss is caused when devices send traffic to an
already overloaded port on a Switch. Flow control prevents packet loss
by inhibiting devices from generating more traffic until the period of
congestion ends.
FTP File Transfer Protocol. A protocol based on TCP/IP for reliable file
transfer.
full duplex A system that allows packets to be transmitted and received at the
same time and, in effect, doubles the potential throughput of a link.
gateway See router .
Gigabit Ethernet IEEE standard 802.3z for 1000 Mbps Ethernet; it is compatible with
existing 10/100 Mbps Ethernet standards.