Federation means a network made of independent servers that talk to each other. There is no single company holding the accounts: each server holds its own, and they exchange messages over a shared protocol.
For anyone reading data out of such a network, that changes three things.
A handle alone is not an address
On a federated network an account is always user@server. Two different people can hold the same local name on two different servers, so @name on its own identifies nobody.
The correct response to a bare handle is to refuse it, not to guess a server. Guessing means silently returning a different person's data, which is the worst possible outcome — so our Mastodon route answers a bare name with a 400 rather than picking an instance.
One server is authoritative, the others have copies
Any server that has seen an account holds a cached view of it. Those copies lag, and their counters can be stale or partial.
| You ask | You get |
|---|---|
| The account's own server | The authoritative numbers |
| Any other server | That server's copy, of unknown age |
So a read has to be directed at the origin instance. A reader that queries whichever server is convenient is measuring cache freshness, not the account.
Local identifiers are local
The same account carries a different numeric id on every server that knows it. The stable identity is the protocol URI — or, on networks that have them, a decentralized identifier. Keying anything on the numeric id means your data breaks the moment you read from a different server.
What it changes about collection
Reading one profile is easy: go to the origin, no key, no account. Searching across the network is a different problem — there is no central index, and post search generally needs an authenticated token on each instance. That asymmetry is why we run the profile and posts routes while not collecting that network for the archive: one is free and account-less, the other is not.
And verification means something else
Federated networks typically verify that an account controls a link, not who the person is. Populating a verified flag from that asserts an identity check the protocol never performs — see verified badge.