GE 90-30 PLC, Руководство пользователя, Страница: 74 / 93

GFK-1322A D-3
D
Glossary of Terms
AUI Port The connector on the network interface.
AUI Cable The cable between the AUI port and the transceiver (some
transceivers plug directly into the AUI port, thus requiring no
separate AUI cable).
Address Administration The assignment of LAN addresses locally or on a universal basis.
Address Field The part of a Protocol Data Unit (PDU) that contains an address.
Address Resolution Protocol The Internet Protocol that binds dynamically a high-level Internet
Address to a low-level physical hardware address such as a MAC
address.
ASCII Code The American Standard Code for Information Interchange is an
information code standard by which digits, letters, symbols and
control characters can be encoded as numbers.
Attachment Unit Interface (AUI) In a network node on a Local Area Network, the interface between
the medium attachment unit (MAU) and the data terminal
equipment. Often called “transceiver cable”.
Bit Contraction of Binary Digit. The smallest unit of memory. Can be
used to store one piece of information that has only two possible
states or values (e.g., One/Zero, On/Off, Yes/No). Data that requires
more than two states or values (e.g., numerical values) requires
multiple bits (see Word).
BOOTP BOOTP is a bootstrap protocol that allows a TCP/IP network node
(such as a Series 90 PLC with Ethernet Interface) to discover its own
IP address, the address of a file server host, and the name of a file to
be loaded into memory and executed. Information is supplied from a
BOOTP Server device on the network.
Broadcast Address A LAN group address that identifies the set of all nodes on a Local
Area Network.
Bridge A functional unit that interconnects two Local Area Networks
(LANs) that use the same logical link control protocol, but may use
different medium access control protocols.
Broadcast Sending of a frame that is intended to be accepted by all other nodes
on the same Local Area Network.
Bus Network A Local Area Network in which there is only one path between any
two network nodes and in which data transmitted by any node is
available to all other nodes connected to the same transmission
medium. NOTE: A bus network may be linear, star, or tree topology.
Byte A group of bits, typically 8 bits, operated on as a single unit. A single
ASCII character typically occupies one byte. (See Octet).
Carrier Sense In a Local Area Network, an ongoing activity of a network node to
detect whether another node is transmitting.
Carrier Sense Multiple Access with
Collision Detection (CSMA/CD) A bus network in which the medium access control protocol requires
carrier sense and in which exception conditions caused by collision
are resolved by retransmission.
Channel A channel is an abstract term used to describe a connection between
a client PLC and a server PLC and the periodic transfer of data
between the two devices.