I don't believe so, not in the strictness sense.
reply> A federated network is a system where independent networks, servers, or organizations agree to follow common standards so they can talk to each other without giving up control to a single central company.
In traditional IRC networks, you end up forming a spanning tree of servers that belong to a common name, "the network". However control remains in the hands of the operators of that network.
The "control" was basically permission to connect (and thus share messages/users/etc) between multiple servers. So I see your point, you couldn't just randomly connect your server to someone else's server in quite the same way email worked, but at the same time the servers could be easily owned by different people running different software.
replybut you could change networks, you could run your own.
replyProtocol was documented but each server is a silo.
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