The fediverse is the network of federated decentralized social media using activitypub to connect. Lemmy (the software on which chapo.chat is based) will be in some months part of this network.
What do you think about fediverse ? Are some of you using Mastodon as a twitter replacement ?
In some ways, yes, in other ways, no.
SMTP is a protocol laid out by the IETF in RFCs. Everyone got together and hammered out the protocol, and everyone agreed to abide by the RFCs so that data could be interchanged between all the independent systems. That's why you can send an e-mail to a Gmail account from an MSN account and it will transit the network and end up on the other end, still able to be processed and displayed.
So, to me, that means that there is interoperability. That's what the IETF strives for.
Lemmy is talking about using ActivePub, which is is being developed by the W3C. It's sort of like the IETF, but at a higher OSI layer. So, that's why they talk about "federation" - so that different lemmy instances can exchange data via ActivityPub. Since I work at a lower layer in the OSI model, that's why I am focusing on the identity federation part of Lemmy, https://en.wikipedia.org/wiki/Federated_identity - and why I don't think it's all that useful to have identities persist across lemmy instances.