3Com 3824 Implementation Guide - Page 94

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.