Update required for Overview of ST 2110 Standards for D2 Appendix_FINAL

[David-P-B]

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In CP0071.Overview of ST 2110 Standards for D2 Appendix_FINAL.docx ST 2059-2:2021 [Ref 13 in doc] has been updated to remove text for timing synchronization requirements.

The text
"synchronization of device reference clocks when there are multiple audio and video devices at the same location should be <1 µs, achieved within 5 s of connection."
was in ST 2059-2:2015, but was removed in ST 2059-2:2021.

The requirements <1 µs, achieved within 5 s of connection is now considered a guideline, but is not necessarily relevant for all media production applications.

Suggested way forward

Replace:
ST 2059-2 also specifies that the synchronization of device reference clocks when there are multiple audio and video devices at the same location should be < 1 µs, achieved within 5 s of connection. The Reference Architecture in the Joint Task Force on Networked Media Phase 2 Report [15] is also relevant to this, as it recommends that for multi-channel audio and image synchronization, time synchronization between media streams should be < 10 µs.

With:
ST 2059-2 [13] originally recommend that the synchronization of device reference clocks when there are multiple audio and video devices at the same location should be < 1 µs, achieved within 5 s of connection. These guidelines were removed form the 2021 update of ST 2059-2, as they not applicable for all media production applications. The Reference Architecture in the Joint Task Force on Networked Media Phase 2 Report [15] still lists these guidelines and recommends, that for multi-channel audio and image synchronization, time synchronization between media streams should be < 10 µs.

Additional context

Largely the industry is still designing ST 2110 networks with these guidelines in mind. They are not employed for more simple contribution use cases or when combing ST 2210 with other networks, such as NDI. Currently < 1us time synchronization is not achievable over a R15 5G Network and may not be achievable over 5G, even with TSN support.

5GMAG_REP_05