Why does the wifi network need to have internet connection to cast local content?

[mvach]

While Chromecast now supports and with apps like Avia, Real, Plex to cast local content why does the wifi network need to have internet connection to cast local content? I travel for work with a portable wifi router(hotel wifi doesn't work)thinking I could create my own non-internet network to cast. Chromecast does not work when not having internet connection. Why? It should perform local network functionality.

 

[Rukbat]

Google's choice.

Does the hotel's wired (Ethernet) network work? Stick that into the WAN port of the router.

 

[mvach]

Yes I have used the hotel ethernet before. But the one I'm staying at of late was recently renovated and they removed the ethernet.

 

[Spec2nirvash]

Because Google servers handle the broadcasting part of Chromecast, me thinks. Seems extremely silly to use Google as a proxy instead of simply broadcasting to a TV a few feet away from you