Does Multiple Google Home devices mean multiple streams or one stram casting to others?

[arkmannj]

Hello,
I was wondering if you have multiple google home devices (say 2 in the kitchen) and you say "Hey Google play music in Kitchen" is each of the home devices have its own stream or is one device getting the stream then casting it to the other device(s) ?

I'm wondering about bandwidth usage. and obviously one stream doesn't take that much bandwidth but having several throughout a house could quickly start consuming a lot if they each are streaming.

Thanks!
~Ark