So lets say there are 100 instances. My instance needs to issue api requests to each instance to sync with the network. They in turn need to issues 100 requests to me to sync (and eachother). What about when there are 100k instances? Its exponential.

This falsely assumes that everything gets federated to everyone, which isn’t the case for ActivityPub. You only get what you actually subscribe to with it.

Mastodon already has those numbers you mention and there are no performance issues in the overall network.

Modern webservers don’t have a problem serving thousands of requests as long as they are spaced out a bit timewise. And since each AP instance only sees and interacts with a small part of the overall network it should not become an issue to expand the network horizontally. It is anyways probably better to think of interconected archipelagos and not of a singular network in the case of ActivityPub.

ActivityPub is designed to scale well for millions of users with a low number of subscribers each (Dunbars number and so on). It is not designed as a mass media publishing tool where a few have tens of thousands or even millions of followers.

I consider this a feature, but feel free to disagree.

This depends on what you think the purpose of ActivityPub is and subsequently the type of scale. ActivityPub is designed for horizontal scale in a “social network”. If you have lots of participating entities with a more or less similar number of interconnected subscriptions ActivityPub scales extremely well, unlike ATProto, which needs to more or less ingest the entire network in its firehose.

But you are right that ATProto is better designed for “social media”, meaning that most subscriptions are one sided affairs with highly visible “influencers” being the main point around which the network operates. Obviously this is what most commercial networks are more interested in as it allows profitable advertisement and other forms of social influence.

I see these two types as entirely different forms of social interaction, and couldn’t care less about the latter. So I am not worried at all about scaling issues of ActivityPub, as it scales extremely well in the “social network” type of interaction.

Hmm, afaik other than some generated small thumbnails no remotely sourced images are stored on your server when you turn off the proxy. At least in theory, but the entire Pictrs integration in Lemmy is such a mess with random unexpected behavior that at this point I am hesitant to claim that no remote images ever get stored (there seem to be alternative code paths for specific image hosts like Imgur and crap like that).

The main issue with hosting your own fediverse instance is that federation doesn’t happen by itself and you need to quite actively search for accounts to subscribe to so that the servers start talking to each other.

I am not sure OP is asking about hosting a Lemmy instance though. They mention non-Lemmy fediverse software.

However I think you misunderstood how proxying works:

Note that this has been drastically reduced with the image proxying, where if someone on say, .world posts CSAM it’s proxied through my server but not hosted by my server. So, liability is still a thing, but as long as the admins of .world take action then i’m protected with them. If proxying is disabled then the CSAM would live on my server too - and that means I’m legally required to report it.

It is actually pretty much the oposite of what you describe. The image proxy in Lemmy is a user privacy feature, but it comes with the downside that the server does indeed download and temporarily stores all media that are requested through it.

No, this isn’t about individual persons turning bad or something silly like that. You can’t have a little decentralization either, for economic reasons. Once you get large instances in a supposedly decentralized network these by necessity need to professionalize sooner or later. Which means they need to find investors and a way to gain income from it. And then the enshittification commences… it is naive to believe that you as the founder are immune to that and if you try to resist it, the investors and other staff will find a way to push you out.

I was thinking about activity tracking stuff like Wanderer or DiveDB… as my Flohmarkt instance would be also more outdoor stuff themed. But yes event management stuff like Mobilizon or Ganzio, or (non-federated) Lauti or Karrot might be an interesting option as well.

No one talks about only one possible alternative, but it is often not immediately obvious to laypersons why a defense mechanism is vital to have and can not be made a middle ground. Like for example there is no way to weaken end to end encryption a little bit to scan for CSAM, without breaking it entirely.

This assumes all these hundreds of pages are exactly the same and can be automated with bots without anyone noticing immediately.

There is a reason why spam on the Fediverse almost exclusively comes from a few large generic servers.

Maybe those European buyers were using the US/global page of ebay? The German ebay is an entirely different legal entity and (at least when I last used it) didn’t interact with anything other than what happened on their website for Germany only. Maybe it works differently in Canada, no idea.

I actually typed 99.999% first, but then decided some stickler would for sure question that number then 🤦

The point is that operating on hundreds of different pages that each have limited reach and interact only in a limited fashion in a way that isn’t a problem for legitimate users but severely limits the volume spammers can reach is a lot of work. Spam only makes sense when it is cheap to do and high volume.

Well, this is a more philosophical question, but it is a result of misaligned incentives and not because someone is having some evil master-plan. Most of today’s Facebook like sites didn’t start out as evil empires, they became so basically by necessity once they chose a certain trajectory. The only way to prevent that is to have strong defense mechanisms in place from the very beginning and that then can easily appear as the other extreme.

Which is location specific for Germany, no? But yes I have never used it.

They are asking how it works, and when you explain it to them they say: “that is bad design, why can’t it be more like X?” With X being exactly what Flohmarkt wants to avoid.

Spam is about reach, as 99.9% of the recipients will not buy anything from a spammer. Obviously the location specificity of Flohmarkt doesn’t prevent other forms of abuse, but it makes Flohmarkt instances very unattractive for commercial spammers as you can’t reach a sufficiently broad user-base with your relatively generic ads.

Because people are asking for things that are explicit anti-features from centralized commercial platforms that aim for platform feudalism like Amazon and Alibaba. Flohmarkt explicitly doesn’t want to replicate these and aims to be a decentralized network of location specific classified pages. Obviously there can’t be an agreement when people ask of the anti-facebook to be more like Facebook 🙄

It certainly did here in Europe.