GE 90-30 PLC Switch User Manual

Appendix A Glossary
IEEE 802.3 CSMA/CD (Ethernet) MAC and Physical Layer standard.
IEEE 802.4 Token Bus (MAP LANs) MAC and Physical Layer standard.
IEEE 802.5 Token Ring (IBM) MAC and Physical Layer standard.
Information Field That part of a protocol data unit (PDU) that contains data, as
opposed to the address field and command field.
Initiating Station The station from which an instance of communication (a transaction)
originates. Also referred to as “client”.
Interface Shortened form for “Ethernet Interface”. The general term used in this
manual to identify the GEnet hardware module, with or without software, that
connects a PLC (or CNC) to a network. (See also LAN Interface.)
Internet Any collection of networks and gateways that use the TCP/IP protocols and
function as a single, cooperative virtual network, specifically, the world-wide
Connected Internet
Internet Address A unique Internet address identifies each node on an IP network (or
system of connected networks). The Internet address is assigned to the node by the
user. (Also known as an IP address.) (See also Physical Address.)
Internet Control Message Protocol (ICMP) The Internet Protocol that handles error and
control messages.
Internet Protocol (IP) The Internet standard protocol that defines the Internet datagram
and provides the basis for the Internet packet delivery service. See also
Transmission Control Protocol (TCP).
Inter Repeater Link (IRL) A mechanism for interconnecting two and only two repeater
IP Address See Internet Address.
Jabber A transmission by a network node beyond the time interval allowed by the
LAN Interface A term used in this manual to identify the GEnet hardware module,
with or without software, that connects a PLC or CNC to a network.
LAN Interface Status Bits (LIS Bits) The LIS bits comprise bits 1-16 of an 80-bit status
bit area. The location of this 80-bit status area is assigned using the Logicmaster 90
Configuration Package or CIMPLICITY Control in the “Status Address” field. The
LIS bits contain information on the status of the Local Area Network (LAN) and the
Ethernet Interface itself.
Linear Topology A network topology in which nodes are each connected at a point
along a common continuous cable which has no loops and only two endpoints.
Link Service Access Point (LSAP) A Data Link layer SAP. A single byte that identifies
the routing of data received by the network node.
Local Address Administration Address administration in which all LAN individual
addresses are unique within the same Local Area Network. (See also, Global
Address Administration.)
Local Area Network (LAN) A computer network located on a user’s premises within a
limited geographical area.