A UAFX Station supporting gPTP time synchronisation as defined in IEEE Std 802.1AS2020 shall conform to IEEE Std 802.1AS2020, 5 with the definitions specified in 7.4.2.2.2, 7.4.2.2.3, and 7.4.2.2.4.
NOTE Clocks are currently not modelled in OPC UA, and it is a vendor decision to select a gPTP domain for use at the application layer if multiple gPTP domains are supported. Clock representation in OPC UA needs to be added in a future release for UAFX.
A UAFX Station supporting gPTP time synchronisation shall support at least two gPTP domains in a Bridge Component for Working Clock and Global Time and at least one gPTP domain in an End Station Component for Working Clock or Global Time.
The gPTP message priority is defined in IEEE Std 802.1AS2020, 8.4.4.
It is recommended that gPTP messages are transmitted using the traffic class associated with Network Control as defined in Table 1 and derived from 6.4.3.
NOTE IEEE Std 802.1AS2020 defines gPTP messages to be transmitted untagged, i.e., frames do not carry priority information for traffic class selection. At the same time, IEEE Std 802.1AS2020 neither specifies a well-defined device-internal priority nor management capabilities for the configuration of the traffic class to be used for the transmission of gPTP messages.
A UAFX Station supporting remote management (see 6.2) and gPTP time synchronisation shall implement gPTP management for the managed objects defined in IEEE Std 802.1AS2020, 14.
Bibliography
IEEE Std 1588-2019 – Precision Clock Synchronization Protocol for Networked Measurement and Control Systems
https://standards.ieee.org/standard/1588-2019.html
IEEE Std 1588-2019 – Precision Clock Synchronization Protocol for Networked Measurement and Control Systems
https://standards.ieee.org/standard/1588-2019.html
OPC 10000-84, OPC Unified Architecture– Part 84: UAFX Profiles
http://www.opcfoundation.org/UA/Part84/
IEC/IEEE 60802 – Time-Sensitive Networking Profile for Industrial Automation
https://1.ieee802.org/tsn/iec-ieee-60802/
OPC 1000083, OPC Unified Architecture – Part 83: UAFX OfflineEngineering
http://www.opcfoundation.org/UA/Part83/
OPC 10000-100, OPC Unified Architecture– Part 100: Devices
http://www.opcfoundation.org/UA/Part100/
IETF RFC 4594 – Configuration Guidelines for DiffServ Service Classes, August 2006
https://www.rfc-editor.org/rfc/pdfrfc/rfc4594.txt.pdf
IETF RFC 3246 – An Expedited Forwarding PHB (Per-Hop Behavior), March 2002
https://www.rfc-editor.org/rfc/pdfrfc/rfc3246.txt.pdfhttps://www.rfc-editor.org/rfc/pdfrfc/rfc3246.txt.pdf
IETF RFC 8343 – A YANG Data Model for Interface Management, March 2018
https://www.rfc-editor.org/rfc/pdfrfc/rfc8343.txt.pdf
IEEE Std 802.1AS-2011 – IEEE Standard for Local and Metropolitan Area Networks – Timing and Synchronisation for Time-Sensitive Applications in Bridged Local Area Networks
https://standards.ieee.org/standard/802_1AS-2011.html
IEEE Draft Std P802.1ASdn – Draft Standard for Local and Metropolitan Area Networks: Timing and Synchronisation for Time-Sensitive Applications – Amendment: YANG Data Model
https://1.ieee802.org/tsn/802-1asdn/
IETF RFC 6762 – Multicast DNS
https://www.rfc-editor.org/rfc/pdfrfc/rfc6762.txt.pdf
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