Basically, on ATProto, everyone stores their own data on a PDS (Personal Data Server). This includes every post, image, video, follow, like, block, etc. The relay crawls the open web for PDSs to consolidate into a single stream of data.

From here, services can build off of that single data stream without needing to do any crawling of their own.

Of course, this does give the operator of the relay a lot of power. If they were to block your PDS, then only services relying on a different relay can access your data. This is especially why it is important that there exist independent third-party relays, but no one has taken up the mantle yet.

[–] merc@sh.itjust.works 3 points 18 hours ago

The PDS design is a nice approach to making AT Proto distributed. But, the way they chose to operate relays means that the protocol requires massive investment to run.

The absolute minimum spend for a node right now, even with Bluesky still growing, is something like tens of thousands of dollars per year. If Bluesky does become the next Twitter, it will probably be $100k+ per year to run a relay. That means a company could run a relay, maybe a university could run one, but it's way out of the reach of anyone but the richest of individual users.

[–] Flax_vert@feddit.uk 2 points 19 hours ago (1 children)

Can't someone theoretically make an Activitypub relay which hosts information from all private instances that federate with it? Like, how is this (AT Protocol) better

[–] The_Decryptor@aussie.zone 3 points 15 hours ago (1 children)

They already exist, they range from smaller webring like relays to ones that tie the major nodes together.

[–] airportline@lemm.ee 1 points 2 hours ago

Neat! Does that mean there's an ActivityPub equivalent to the ATProto Firehose?