Rockwell Automation 2711-K9A10_K9C10_T9A10_T9C10 DeviceNet Communications User Guide - Manual (Page 36)

Publication 2711-6.0.4
Glossary
Assembly Object
DeviceNet products usually have one or more Assembly Objects. The
purpose of the Assembly Object is to group different Attributes (data) so
they can be moved by a single message. See also: Instance
Attribute
A data element that can be read or written. Each attribute is assigned an
integer value (Attribute ID) as an identifier in the range of 0-255.
CAN
Acronym for Controller Area Network. DeviceNet is based on CAN.
CAN ID
or identifier is an 11-bit field that identifies each message on any CAN
network. CAN IDs must be unique.
Class
A set of objects that behave in a similar manner. Each object class is
assigned an integer value called the Class ID (0-65535). Classes 0-99 are
open, classes 100-199 are vendor specific. Higher numbers are divided
between open, reserved and vendor specific, but are currently rarely used.
Vendor specific classes are defined by the vendor.
Client
The device that originates a transmission. Applies to Explicit Messaging.
With Explicit Client messaging, the PanelView terminal is the client device
that requests or sends information from/to a server device. See Server.
Connection
The logical link between a node and one or more other nodes (for production
or consumption). Most nodes have at least two connections (one explicit,
one I/O).
COS
Acronym for Change of State. I/O messages are sent when data changes. If
no change of state occurs, messages are sent at a pre-determined (heartbeat)
interval.
Cyclic
I/O messages that are sent at a predefined fixed rate.
DeviceNet
DeviceNet is an open network standard based on CAN (Controller Area
network). The specification and protocol are open. Vendors are not required
to purchase hardware, software or licensing rights to connect devices to a
system. Anyone may obtain the DeviceNet Specification from the Open
DeviceNet Vendor Association, Inc. (ODVA) for a nominal reproduction
charge (http://www.odva.org).