94 GLOSSARY
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.
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.
protocol A set of rules for communication between devices on a network. The
rules dictate format, timing, sequencing and error control.
RADIUS Remote Authentication Dial-In User Service. An industry standard
protocol for carrying authentication, authorization and configuration
information between a network device and a shared authentication
server.