Federating servers
2026-05-07 18:51 UTC
So, one part of the popular imagination about ActivityPub I've seen is the idea of server federation.
I think the idea is that if two servers have interacted in some way, all (?) public (?) content from one server will be sent to the other server, and vice versa.
This comes up a lot with new servers; people ask to have a post shared broadly so that their server rubs shoulders with others, getting the federated feed flow going.
ActivityPub does in fact have a mechanism defined for this:
Additionally, if an object is addressed to the Public special collection, a server MAY deliver that object to all known sharedInbox endpoints on the network.
As far as I've seen, most (?) servers don't implement this; it would overwhelm small servers pretty quickly.
However, some (?) servers do implement it for some (?) activities, especially profile update and delete activities.
Is this the origin of the idea that new servers need to have their content shared around? Are people misunderstanding the way that relays work? Is it just a trick to get your content shared?
Replies (2)
-
@rimu@piefed.social 2026-05-07 21:23
In FEP 1b12, that is what occurs (most of the time) - as soon as an instance has a dozen users their interests will be varied enough that almost every active community in the threadiverse is subscribed to and they’ll be receiving almost all the traffic. It works out ok at our current scale (small).
-
@evan@activitypub.space 2026-05-07 18:58
Another possibility is that when someone asks to have their content shared, that will result in a few Follow requests, which does result in their future content being distributed to other servers (and public content goes to Fediverse and hashtag feeds). So, it seems like the sharing is what got the distribution going, even though it is indirect (sharing causes following causes appearing in the Fediverse feed).