56 GLOSSARY
information to forward packets based on their destination address. This
process is known as filtering.
broadcast A packet sent to all devices on a network.
broadcast storm Multiple simultaneous broadcasts that typically absorb all the available
network bandwidth and can cause a network to fail. Broadcast storms
can be due to faulty network devices.
collision AtermusedtodescribetwocollidingpacketsinanEthernetnetwork.
Collisions are a part of normal Ethernet operation, but a sudden
prolonged increase in the number of collisions can indicate a problem
with a device, particularly if it is not accompanied by a general increase
in traffic.
CSMA/CD Carrier-sense Multiple Access with Collision Detection. The protocol
defined in Ethernet and IEEE 802.3 standards in which devices transmit
only after finding a data channel clear for a period of time. When two
devices transmit simultaneously, a collision occurs and the colliding
devices delay their retransmissions for a random length of time.
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 10Mbps 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.
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 congestion control mechanism. Congestion is caused by devices
sending traffic to already overloaded port on a Switch. Flow control
prevents packet loss and inhibits devices from generating more traffic
until the period of congestion ends.
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