The Hue Bridge is capable of working entirely locally--no Internet connection needed (for anything besides optional firmware updates and, of course, out-of-home control unless you use a VPN or similar to get back in). Philips also seems to be pushing towards an HTTPS API for local/LAN communication, though most integrations probably still use HTTP.
I'm not sure what your specific concerns are, but maybe one or both of these is helpful information for you.
Maybe the issues with CT and level not always getting set? (But yes, not clear to me if they meant the routing isssue or this issue that I brought up without being asked to. 
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