CORS requirements can be misread about is-04 HOT 4 OPEN

Admittedly the testing tool is the only client I'm aware of that is explicitly checking for CORS headers.

I am aware of a commercially available controller that is developed on top of .NET / ASP.NET and always sends CORS server headers based on their interpretation of the current specification (and likely previous testing tool behaviour). As mentioned previously I know from experience that is not default behaviour for the framework, and so the developers would have had to go though some hoops to override that.

from is-04.

Thanks for the follow up. I agree with your assessment of the specs.

some NMOS client implementations expect server to always send CORS headers.

Without naming names, are you aware of controllers that expect these headers, not just the testing tool (previous to the fix by AMWA-TV/nmos-testing#724)?

from is-04.

Architecture Review Group review: place on backlog

from is-04.