GE 90-30 PLC - Manual (Page 89)

A
A-6 TCP/IP Ethernet Communications User’s Manual - August 1997 GFK-1084B
Local Station The station at your immediate location, i.e., “here”. (See also “Remote Station”).
Log Events Events recorded in the system exception log for the LAN Interface. The
maximum number of events in the exception log is 16.
Logical Link Control (LLC) Protocol In a Local Area Network, the protocol that
governs the exchange of frames between network nodes independently of how the
transmission medium is shared.
MAC Address The Medium Access Control (MAC) address is a 12–digit hexadecimal
number that identifies a node on a local network. Each Ethernet Interface has its
own unique MAC address.
Medium Access Control (MAC) In a local area network (LAN), the part of the protocol
that governs access to the transmission medium independently of the physical
characteristics of the medium, but taking into account the topological aspects of the
network, in order to enable the exchange of data between network nodes.
Medium Access Control Protocol In a Local Area Network, the protocol that governs
access to the transmission medium, taking into account the topological aspects of the
network, to enable the exchange of data between network nodes.
Medium Attachment Unit (MAU) In a network node on a Local Area Network, a
device used to couple the data terminal equipment (DTE) to the transmission
medium. Often called “transceiver”. The MAU may be built into the DTE or it may
be a separate unit that attaches to the DTE through an AUI.
Multicast Address A LAN group address that identifies a subset of the network nodes
on a Local Area Network.
Netid The netid is the part of the IP address identifying the network on which the node
resides. (See also Hostid.)
Network An arrangement of nodes and interconnecting branches.
Node The physical module that connects a node to the network. The Ethernet
Interface is an example of a node. It connects a station (PLC or CNC) to a network
(Factory LAN). A station may contain more than one Ethernet Interface and
therefore contain more than one node.
Octet A group of 8 bits operated on as a single unit. (See also Byte.)
One–Way Propagation Time See Transmission Path Delay.
Path The sequence of segments and repeaters providing the connectivity between two
DTEs. In CSMA/CD networks, there is one and only one path between any two DTEs.
Peer Another entity at the same level (layer) in the communication hierarchy.
Peer–Peer Communication between nodes at the same level or layer in the hierarchy.
Physical Address The unique physical layer address associated with a particular node
on the Local Area Network (LAN). Ethernet physical addresses are typically
assigned by the manufacturer. (See for comparison, Internet Address.)
Protocol A set of rules for exchanging messages between two communicating processes.
Protocol Data Unit (PDU) Information that is delivered as a unit between peer entities
of a local area network (LAN) and that contains control information, address
information, and may contain data.