I am hoping that you can provide me with a bit of clarity that I can provide back to my network team. One of the returned values when you query endpoints.office.com is a field that says express route which contains either a true or a false. Does anyone know exactly what this field means? I suspect it doesn't mean that the ips / urls are only required if you have express route implemented, but I'd love to be able to say for sure exactly what that field means.
Attached is a screen shot of that field highlighted for reference
I had read that before, but I still have a bit of trouble with that wording. Does that mean that if you do not have express route, you do not need to configure those IPs in the firewall or if you do have express route then these IPs would be directed over that connection. We do not have Express Route and so this is causing some uncertainty as to whether or not we need them.
I see the same listing of Express Route: True under the TCP and UDP high ports for Skype for Business which I know to be required if you have hybrid setup. This is what makes me think they need to be open and that is only to denote that if you had express route then these would need to be routed over that.