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

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LOSSARY
loop An event that occurs when two network devices are connected by
more than one path, thereby causing packets to repeatedly cycle
around the network and not reach their destination.
MAC Media Access Control. A protocol specified by the IEEE for determining
which devices have access to a network at any one time.
MAC address Media Access Control address; also called hardware or physical address.
A layer 2 address associated with a particular network device. Most
devices that connect to a LAN have a MAC address assigned to them
as they are used to identify other devices in a network. MAC addresses
are 6 bytes long.
main port The port in a resilient link that carries data traffic in normal operating
conditions.
MDI Medium Dependent Interface. An Ethernet port connection where the
transmitter of one device is connected to the receiver of another
device.
MDI-X Medium Dependent Interface Cross-over. An Ethernet port connection
where the internal transmit and receive lines are crossed.
MIB Management Information Base. A collection of information about the
management characteristics and parameters of a networking device.
MIBs are used by the Simple Network Management Protocol (SNMP) to
gather information about the devices on a network. The Switch
contains its own internal MIB.
multicast A packet sent to a specific group of endstations on a network.
multicast filtering A system that allows a network device to only forward multicast traffic
to an endstation if it has registered that it would like to receive that
traffic.
Network Login A port security feature that controls user access at the network edge by
blocking or unblocking access on a per-port basis.
NIC Network Interface Card. A circuit board installed in an endstation that
allows it to be connected to a network.
POST Power On Self Test. An internal test that a Switch carries out when it is
powered-up.