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2. Terms and Definitions
Below is a list of terms used in this manual and their definitions.
Term
Description / Definition
Node
It refers to a relay point, a branch point or a terminal on an EtherNet/IP
network comprised of equipment having an EtherNet/IP port. Devices
with one EtherNet/IP port are recognized as one node on the
EtherNet/IP network, and devices with two EtherNet/IP ports are
recognized as two nodes.
Tag
A tag is a unit that is used to exchange data with tag data links. Data is
exchanged between the network variable specified in "Tag" and the
partner device network variable or the specified I/O memory area.
Tag Set
When a connection is established, from 1 to 8 tags (including Controller
status) is configured as a set. This is referred to as a Tag Set. Each tag
set represents the unit of data that is linked for a tag data link
connection. A Tag data link is established by connecting individual tag
sets. A Tag set name must be given to each tag set.
Tag Data Link
The Implicit communication of the EtherNet/IP standard is called a Tag
Data Link. A Tag data link is a function to exchange data for each tag
cyclically between controllers or between a controller and other device
type on an EtherNet/IP network.
Connection
A connection is a unit of data exchange that ensures data
synchronization.
Connection type
You can select a multi-cast connection or unicast (point-to-point)
connection as the connection type in the tag data link connection
settings. The multi-cast connection sends an output tag set in one
packet to more than one node. The unicast connection separately sends
one output tag set to each node. Therefore, multi-cast connections can
decrease the communications load if one output tag set is sent to
multiple nodes.
Originator and
Target
In order to perform tag data linking, it is necessary to first establish a
connection between the nodes that perform tag data linking. The node
that requests the connection is called the Originator and the node that
receives the request is called the Target.
Tag Data Link
Parameters
In tag data link setting, "tag setting", "tag set setting" and "connection
setting" are collectively called "tag data link parameters".
EDS file
It is a file describing device-specific information such as the number of
input/output points for an EtherNet/IP device.
