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Networking Terminology 1-3
A Segment is the length of Ethernet cable connected to a
port, whether this cable is 10BASE-T, 10BASE-2
(Coax) , or other type. When you daisy-chain
equipment together with 10BASE-2 (Coax) cable, all
of the cable forms a single segment.
Packets are the units of information your workstations and
other equipment send to each other over the
network. A Frame is the data part of a packet. It is
the information that is seen by the hub.
Collisions are a p art of normal Ethernet operation and occur
if two or more devices attempt to transmit at the
same time. A sudden sustained 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. On coaxial segments an
increase in collisions can also indicate faulty cabling.
Device is a term that is usually used to refer to a piece of
network equipment. Every device has a unique
address that is used to identify it on the network.
SNMP (Simple Network Management Protocol) is a
protocol that controls how a management station
gains information from a device. SNMP provides:
■
A set of rules that defin e how a m anagement
station can communicate with a device.
■
A
MIB (Management Information Base)
that
defines what information can be obtained from
the device by the management station. Every
SNMP-manageable device has a MIB, which is a
list of information about it.
■
Unsolicited messages called
Traps
, which work
differently to the usual request/reply
management communication. You can
configure a device so that it generates a trap if a
certain condition occurs, for example a port
partitioning. The trap is sent to the management
station to inform it of the occurrence.
16710.bk : GETSTART.FRM Page 3 Tuesday, October 7, 1997 11:38 AM