I have some RLC-420 cameras that work pretty good and I block their access to the internet ... and they copy the files using ftp to my local server ... on the o

I have some RLC-420 cameras that work pretty good and I block their access to the internet ... and they copy the files using ftp to my local server ... on the other hand, I just got a Chromecast and I'm looking for a way to block them from accessing any Google servers.