@kumicota
Yeah, so right now if you run a mastodon server it connects to existing ones by default, and you have to specify which other servers you want to block, this is called a blacklist.

Some people are talking about giving servers the option of a whitelist, which means the server won't connect to anything that isn't on that list. This means that federation is broken by default, because you have to explicitly say what servers you connect to. I hope it doesn't happen.