Rockwell Automation 1734-ACNR POINT I/O ControlNet Adapter User Manual - Manual (Page 10)

Publication 1734-UM008B-EN-P - August 2005
Preface P-4
Terminology The following table lists ControlNet terminology used throughout this
manual.
Term Meaning
Actual Packet Interval (API) The measure of how frequently a specific
connection produces its data.
Connection ID (CID) An identifier assigned to a transmission
that is associated with a particular
connection between producers and
consumers that identifies a specific piece of
application information.
Network Update Time (NUT) Repetitive time interval in which data can
be sent on the link.
Requested Packet Interval (RPI) The measure of how frequently the
originating application requires the
transmission of data from the target
application.
Scheduled Data transfers that occur in a deterministic
and repeatable manner on predefined NUTs.
Unconnected Service The messaging service that does not rely on
the set-up of a connection between devices
before allowing information exchanges.
Unscheduled Data transfer that use the remaining time in
the NUT after the scheduled transfers have
been completed.