Inherently isn’t the data stored and kept everywhere it’s accessed? If you’re in Germany and are a German your message sent to me just now also now is being stored where I’m located to even read it, no?

In terms of this discussion, stored doesn't mean on an end user device, nor in ram on servers, or temp caching, while serving content.

You guys are just playing with semantics.

In terms of this context, easiest way would be to shard db infrastructure. Not even a remotely big deal for Facebook, with their size.

Hell, they should already want this, to avoid costly, and high ping time, intercontinental links.

But oh nooos, so hard to do. Absurd.

It’s not semantics, though. If I saved everything I ever read onto a database, indexed uniquely by website schema, how does anything change? The point is the same.

I don't get what you are saying. DB schema is irrelevant in terms of where the database backend is stored.

My point is I could just as well have a local database and permanently persist everything I see on the web, no? The same point applies.

Think about internet archive, BitTorrent dumps of Facebook, etc.

This is where lawyers, regulators, and engineers can reasonably disagree with very serious consequences for governments, shareholders, and ultimately citizens.

If you're in a given geography/regulatory regime, and you read something on your smart phone, technically you were served that via some cell tower or ISP, those bits transited that infrastructure. In the US there's a massive clot of regulatory blockage working it's way slowly through the bowels of government around the term of art: "common carrier".

As with many things that devolve into nitpicking, there is a deeper issue: the EU is increasingly regretting becoming the host to, ironically, European-style colonialism on large-scale consumer Internet platforms. The PRC has its own Google, Twitter, Facebook, etc. The EU has Google, Twitter, Facebook, etc. and doesn't love that US companies and regulators are kind of driving the digital lives of the citizens.

The proximate tussle is about the durability of the storage involved. As a European regulator I might be much more comfortable with a write-through cache like TAO holding messages, or FBIDs of messages, including a German in the chat than I am with all such chats being held on a DFS in Prineville among other places, and having them ground over by a Spark or Hadoop job in Forest City among other places.

They'll kick it around and come up with some compromise that will serve end-users by accident at best. Europe won't develop a homegrown consumer Internet industry in our lifetimes. The odds are both US and EU legislators and regulators will miss a step and it'll be ByteDance everywhere by the time anyone reads this :)

Not on their servers though. If the data is in your browser, it's not trivial for e.g. Facebook to then go an do nefarious things with that data at scale. This is how I understand it.

My point isn’t Facebook in particular, but more generally around data residency. Inherently data must be saved and stored to all who access, no?

Wouldn’t the true solution simply be for those who don’t want other regions to save to simply not have access, e.g firewall?

My understanding was that it's about where the data resides. That assumption may or may not be true. But if it is it's feasible for EU data to be stored in the EU and US users request that data from the EU server. Again, my understanding was that this would be a valid way to handle that data but I might be wrong.

Your understanding is correct, but my point is that inherently if US people can access EU profiles inherently some EU data will be stored in the US.

It would then been trivial for someone to crawl EU pages and rebuild the corpus of data.

The only real solution is to firewall off regions and prevent those users from accessing anything other than their own.

This is already what some countries like China do, for instance

I don't think this is what the EU is requiring even though it is possible to scrape EU data. Facebook is pretty good at preventing scraping though.

That is correct, as well as caching.

I'm sure we'd all benefit from hearing the TurtleCoin guy expound on how one goes about multi-national regulation of terrabits/s of multi-layered write-through caching ranging from extremely cold storage on custom hardware to the POP sitting in a Munich suburb and where exactly the line should be drawn on data custody in that setting.

Enlighten us?

That's one issue. Another more complicated issue is which country's legal authority does the owner of the data have to respond to. If the answer is USA, then the data can be requested by this government regardless of where it's stored...