3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in OPC 100004, OPC 10000-80, OPC 10000-100, IEEE Std 8022014, IEEE Std 802.1AS2020, IEEE Std 802.1AB2016, IEEE Std 802.1Q2022, IEEE Std 1588, as well as the following apply.

All used terms are italicised in this document as described in OPC 100001.

3.1.1 Bridge

system that includes Media Access Control (MAC) Bridge or Virtual Local Area Network(VLAN) Bridge component functionality.

[SOURCE: IEEE Std 802.1Q2022, 3.24]

3.1.2 Bridge Component

set of Bridge functionalities necessary for acting as a traffic relay station in a network

3.1.3 end station

A functional unit in an IEEE 802® network that acts as a source of, and/or destination for, link layer data traffic carried on the network

[SOURCE: IEEE Std 8022014, 3.1]

3.1.4 End Station Component

implementation of an end station

3.1.5 Global Time

synchronised time in a network clock derived from a gPTP domain that is traceable to International Atomic Time

3.1.6 Grandmaster Clock

in the context of a single PTP domain, the synchronized time of a PTP Instance that is the source of time to which all other PTP Instances in the domain are synchronized

[SOURCE] IEEE Std 802.1AS2020, 3.14

3.1.7 Grandmaster PTP Instance

PTP Instance containing the Grandmaster Clock[SOURCE IEEE Std 802.1AS2020, 3.14]

3.1.8 IA-station

material element or assembly composed of one or more End Station Components and zero or more Bridge Components

3.1.9 PTP End Instance

PTP Instance that has exactly one PTP Port

[SOURCE: IEEE Std 802.1AS 2020, 3.21]

3.1.10 PTP Instance

instance of the IEEE 802.1AS protocol, operating in a single time-aware system within exactly one domain.

Note 1 to entry: A PTP Instance implements the portions of IEEE Std 802.1AS indicated as applicable to either a PTP Relay Instance or a PTP End Instance.

[SOURCE: IEEE Std 802.1AS2020, 3.22]

3.1.11 PTP Relay Instance

PTP Instance that is capable of communicating synchronized time received on one PTP Port to other PTP Ports, using the IEEE 802.1AS protocol

[SOURCE: IEEE Std 802.1AS2020, 3.24]

3.1.12 UAFX Application

OPC UA Application that includes UAFX functionality

3.1.13 UAFX Station

IAstation supporting the OPC UA FX communication and application layer

3.1.14 Working Clock

synchronised time in a network clock derived from a gPTP domain that is traceable to an arbitrary timescale or to the PTP timescale

Note 1 to entry In general, the Working Clock time is traceable to an arbitrary timescale; however, the Working Clock time can be correlated to a recognised timing standard.