this post was submitted on 04 Jun 2025
110 points (99.1% liked)
Fediverse
34115 readers
702 users here now
A community to talk about the Fediverse and all it's related services using ActivityPub (Mastodon, Lemmy, KBin, etc).
If you wanted to get help with moderating your own community then head over to !moderators@lemmy.world!
Rules
- Posts must be on topic.
- Be respectful of others.
- Cite the sources used for graphs and other statistics.
- Follow the general Lemmy.world rules.
Learn more at these websites: Join The Fediverse Wiki, Fediverse.info, Wikipedia Page, The Federation Info (Stats), FediDB (Stats), Sub Rehab (Reddit Migration)
founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Images dont get saved locally on other instances if they host the content? Well that seems like a big flaw in "federation"..
I assume it's an intentional trade-off by the devs to reduce the storage burden. If each instance is a complete mirror of all federated instances then hosting becomes that much more expensive.
It's also an avenue for attacks.
Instances have 3 options. Save it locally, proxy it, or do nothing. Saving every federated image is not feasible for small instances. It's not a fault of the protocol that instance operators don't want to pay a thousand dollars a month for storage. Matrix has this problem, and look what happened to them: tiny instances are expensive to run, so don't flourish.
Not really, it means I can't send every lemmy instance csam.
no, I agree with the above user that it would be better to federate images too, for at least the following reasons:
If I'm not mistaken, Mastodon already does federate images to other instances, so it isn't unheard of.
I think they would need to find a way to address the problem first. Reportedly, these images have been a huge problem here on Lemmy. Several times now.
i heard its a problem, but never saw any. (im not saying its a lie)
Same, same. I can't verify it and I probably don't want to. But I had people assure to me it happened.
That’s credit towards the admins who acted quickly. That’s why you’ll see instances defederate from an instance if their admin is not active and doesn’t take action against illegal content in a reasonable time, because it can quickly get out of hand. Now if content isn’t proxied and is always mirrored, not only will the admin have to defederate from the problem instance, but they will have to go and clean up whatever was copied on their instance as well.
I can't remember the exact details, but I believe the attackers also targeted instances? So it's not just that it happens with certain problematic instances, but everyone could have that uploaded to their media storage. And it can come from arbitrary places. I believe that adds to the problem. And it kind of requires to shut these things down for everyone. Or at least everyone except a few excellent hand-picked instances who cooperate closely, and the moderation tools actually work.
Yes, they've done an excellent job. I just wish they wouldn't have to deal with these things.
(And I also think some of the child protection agencies should finally offer some open-source tool to scan content. Afaik there are still no image classifiers or hash tables I could use for my projects.)
i hope you dont think thats the only reason for defederation.
I never said that was the only reason. We're talking specifically about image proxying vs mirroring in this thread.
sorry
Mastodon purges them after a while though.
Depending on how the admin has pict-rs (the "subsystem" it uses for media) configured, post images can create local copies /thumbnails for image posts. Some instances opt to do that, some don't.
Other images like ones posted a comments, user/community avatars/banners aren't stored anywhere except their home instance.
But yeah, even the limited caching has proven problematic if questionable/illegal content gets posted.