The term "decentralized" was *already* in active use! So Baran was providing "distributed" as the new term! Oh my god THAT'S WHY THE DEFINITION BARAN PROVIDED FOR DECENTRALIZATION WAS SO WEAK
You don't believe me? Let me show you. LET ME SHOW YOU
Here is where Baran defines "decentralization!" We have to read the whole definition!
You're not allowed to stop until we finish EVERY (cotd) let's GOOOO
> The centralized network is obviously vulnerable as destruction of a single central node destroys communication between the end station.
(cotd)
Baran "decentralization" cotd:
> In practice, a mixture of star and mesh components is used to form communication networks.
IN PRACTICE FOR CENTRALIZED SYSTEMS YOU GUYS
(cotd)
Baran "decentralization" cotd:
> For example, type (b) in Fig. 1 shows the hierarchical structure of a set of stars connected in the form of a larger star with an additional link forming a loop.
OH SHIT HE'S STILL TALKING ABOUT CENTRALIZATION FIGURE B IS THE MIDDLE ONE
(cotd)
Baran "decentralization" cotd:
> Such a network is sometimes called a "decentralized" network, because complete reliance upon a single point is not always required.
OKAY WE'RE DONE
But look at it all together! He's talking about how "decentralization" is a term of art but it's still CENTRALIZED
Baran didn't make up the term "decentralized" it already was being used in practice to talk about top-down hierarchical systems! Baran calls this version centralized even if there's a "loop" (a small number of top-level providers)!
YOU GUYS THIS IS NOT HOW WE ARE USING "DECENTRALIZED"
WE are not describing the future of routing small packets in 1964, that is NOT the world we are existing in, where "decentralized" meant a top-down hierarchical structure
When WE talk about "decentralized", we mean roughly a spectrum, with "centralized" on one side and "decentralized" on the other
Now I don't think Bryan Newbold realized that when he pulled his definition from Mark Nottingham who pulled his definition from Paul Baran, that this was the case. I think this is a game of telephone.
(I don't know how Mark Nottingham didn't realize it but that's an aside)
What I DO know is that it means that the entire structure of analyzing decentralization in Mark's paper and Bryan's blogpost thus, in practice, surround a term that is weak because it was FUNDAMENTALLY describing a centralized system, so it could criticize it
The loss of context here is BRUTAL
To conflate the two *automatically* introduces decentralization-washing. I don't think this is intentional, but it explains a lot.
It explains how a "weak" definition of decentralization could come from one of the boldest visions of what that very *idea* could be
Now okay let's point out the irony here because I feel like if I don't I'm being mean. Bryan does say:
> To some degree, I don't really want to spend time in a terminology debate.
And I just did! At length!
But the whole debate this whole time is "is Bluesky decentralized" so we kinda HAVE to
But also what happened was:
- I lay out a strong definition of decentralization; Bluesky doesn't match
- Bryan suggests an alternate definition, pulls
from
- An RFC which despite the title is extremely lukewarm AT BEST about decentralization which pulls from
- A definition describing centralization
And I don't think this was malicious on Bryan's part in the least because I know Bryan well enough to know he's not like that!
I am pretty annoyed at Mark though for quoting this out of context in such a way that it can completely confuse a narrative like this. I'll assume that was a mistake but
The reality is that Bluesky didn't match my definition of decentralization, and I hope it's pretty clear now that the alternate definition supplied was literally one about centralization
And so that cannot possibly be a lower bar that we say "okay maybe Bluesky can pass this one" I am sorry
Let's PLEASE not move the goalposts on "decentralization". Let's certainly not move them back to something that was literally "here's what centralization looks like in practice".
That's what I'm asking for here. That's why I went so goddamned HARD on terminology here.
Let's check the time.
It's 7:30pm where I am. I woke up at 4:30am and resumed work on my blogpost at 5am.
I have been, for the most part, between the blogpost, my job, and this thread, sitting at my computer fighting for decentralization for about 14 hours. It's been like that a lot lately.
I have a reputation at work of being good at pushing others to take off time and they HAVE to take off time OR ELSE and I try to be that way in general. But I am really truly bad at doing so for myself and I know I have crossed my limits for today.
So let's wrap up for *tonight* in a sec
We're about halfway through this blogpost. There's a lot going on in my life. I am trying so hard to keep the organization I work for alive and moving forward. I am tired. I need rest. And I still need to drive two hours across the state tonight.
We're going to resume tomorrow. But first...
There's a reason I'm going really hard on this. I really care a lot about the shape of the internet. And tomorrow we're going to get into some more analysis and a talk about *values*, and one thing I like is that Bryan talked at length about Bluesky's values. And I think that part was really good.
For tonight, I need to unwind, I need to put a label on a mailbox, I need to eat dinner, I need to drive across the state, I need to sleep.
Maybe I appear ridiculous. I get it. I go pretty hardcore on this stuff. If you know me you know I tend to go all in.
I am signing off for the night. Tomorrow we will analyze whether or not my assertion that "ATProto has explosive behavior as it approaches decentralization" problems.
I'm not going to read notifications until I finish this. Maybe someone will prove me wrong before I get it done.
I'll be oblivious.
We will also analyze values, which maybe I care about more than anything. And there will be more secret goblins, hidden among the posts.
For tonight, it's rest time. It's time for a
=== NO MORE LOOKING AT MY COMPUTER BREAK ===
Hello! I am back at my computer. Today we are going to talk about how ATProto does in terms of scaling. Yes, we know it scales up, and has done an impressive job of doing so!
But what about scaling towards decentralization? Does it scale down? And does it scale wide? Let's look.
Before we get deep into that, when we left last night I was extremely tired and had been working at my computer for over 14 hours. I then said I was going to drive two hours across the state that evening.
Thankfully thanks to the support of people who love me, I did not do that foolish thing!
So anyway, I am better rested, and also I woke up to the surprise that our fundraiser is doing a lot better, like by a lot, than it was yesterday, which is nice because I was extremely stressed out https://spritely.institute/donate/
So I am feeling much better and alive and today I remembered to eat lunch
But you probably aren't here to hear about my lunch choices or how much sleep I got or whether or not I forgot to bring my ADHD medication with me (I did so now I am drinking a bunch of caffeine instead), you are probably here to hear the rest of the analysis about decentralization and Bluesky etc
So let us get to it, let's talk about whether or not Bluesky can scale *down* in a meaningful way.
In my last essay I made assertions that this was important for decentralization and said ATProto wasn't great for this, and this was one thing people challenged me on
So let's take a look!
When I say "scale down", what I generally mean is "small instances can generally participate on the network". (We'll talk about "scale wide" later.) But another useful possibility which has come up is "can you make a smaller, more isolated use-case and use the same protocol for it"
This latter version of scale down does come up in Bryan's article:
> A specific form of scale-down which is an important design goal is that folks building new applications (new Lexicons) can "start small", with server needs proportional to the size of their sub-network.
(cotd)
Strictly speaking, I agree, ATProto can scale down in this use case! For example, if you wanted to make a small specialized forum for collaborative storytelling, you could use ATProto for it, and that's true, you could do it
But is it the right choice?
In some ways we are talking about two different things here: extension of functionality (which you might want the same scale for) and having a smaller and more isolated community
But regardless
ATproto positions itself *specifically* as designed for not wanting to miss messages, and I talked previously about how ATProto's design requires a god's-eye view.
It's a bit strange of a choice when you say "let's run a smaller community"
Given that message passing systems handle small scale systems *beautifully*, and *still* allow for interactions with larger scale systems, it's a bit confusing to me *why* you'd choose ATProto for such use cases. What is the specific benefit you'd gain? Especially because it's actually lossier here
At any rate, there's a bit of conflation here. "It scales down" by saying "you can have an isolated community/use case that's oblivious to the rest of the system" is categorically distinct from "it scales down" in terms of "a small node can meaningfully participate with the larger system"
At any rate, the problem with "scaling down" is much clearer when it comes to the problem of "scaling wide".
Or let me put it a different way: ATProto *explodes in complexity* when you try to scale it towards meaningful decentralization
Yes that's right we're getting to the spicy part of this conversation. We did the warm-up, now it's time to talk about the real thing, whether or not decentralization in the way I believe people *think* that term means is reasonably possible with ATProto as it's currently designed
But before we do that, I need to stretch and run to the bathroom
So for those of you following along, if you found this, Secret Goblin #3, let me know: "
Oops wait actually we gotta talk about that one for a sec there's a reason I left it in scare quotes
Why on earth is the textual descriptor for Unicode U+1F47A "JAPANESE GOBLIN", does anyone know?
It's a Tengu, right?
Despite being the only actually named "goblin" emoji, I feel awkward about this one because is it correct to call it a "JAPANESE GOBLIN" instead of just "TENGU"?!?!
I don't know!
If you have knowledge or OPINIONS about "
Otherwise it's time for a
=== STRETCH BREAK ===
I'm back. It's time to talk about it: does Bluesky/ATProto suffer a "quadratic explosion" as we move from centralization towards *meaningful* decentralization?
I claimed it did, but I was challenged on this. What did I mean? Am I right or wrong?
It's time to find out!
In the previous blogpost I said the following:
> If this sounds infeasible to do in our metaphorical domestic environment, that's because it is. A world of full self-hosting is not possible with Bluesky.
(cotd)
Decentralized ATProto is quadratic quote, cotd:
> In fact, it is worse than the storage requirements, because the message delivery requirements become quadratic at the scale of full decentralization: to send a message to one user is to send a message to all. Rather than writing one letter, a copy of that letter must be made and delivered to every person on earth.
This was probably the thing I got the hardest pushback on from a team member of Bluesky, that it is not quadratic as we scale towards decentralization.
Truth be told, I don't have a degree in CS. Most of what I know I learned from studying independently and community resources. Was I wrong?
Just as a quick aside, regarding that comment about "agency", maximizing the agency of everyone (and more importantly, minimizing subjection!) sits at the heart of my ethical framework https://fossandcrafts.org/episodes/11-an-ethics-of-agency.html
So I don't disagree on that part, but that's an aside!
Now, I said I won't read replies until I am done summarizing things, and that's true, so maybe someone has gone out of their way and proven that I am wrong, that the claims in my article are factually incorrect and so on and so forth. I wouldn't know yet.
But... I don't think I'm wrong.
As said I'm very self-conscious about these things because I *don't* have formal CS training. But I do a lot of research and so I've tried to become knowledgeable about these things and this *seemed* like the correct analysis to me
Because of that, I turned to people who actually knew more than me
For one thing I derailed the entire Spritely morning standup by walking everyone through the scenario. I gave the story example, which I'll detail later.
But @dthompson didn't find the story helpful, too much narrative detail. "I need to work through this example independently." So he did.
@dthompson came back and laid it out in more formal terms and said I was right.
But I was still nervous, so I called up one of my old MIT AI Lab type friends and rambled about it to them on a call. What did they think?
"I think it's pretty clear immediately that it's quadratic. This is basic engineering considerations, the first thing you do when you start designing a system," they said.
Well that's a relief, why isn't it clear to everyone else, I asked?
So they suggested I lay it out to you as I did to them.
Let's start with the following:
- ATProto has positioned itself as "no compromises on centralized use cases". Well, in that case, let's say it can't do *worse* than eg ActivityPub. This includes with replies. You can't do *worse* than ActivityPub on replies and mentioning someone, etc.
- We will interpret the most centralized system as one where there's only one provider for storage and distribution of all messages: the least amount of user participation
- The flip side of the spectrum of maximum decentralization is the *most* amount of participation: every user self-hosts.
- Just as blogging is decentralized but Google (and Google Reader) are not, it is not enough to have just PDS'es in Bluesky be self-hosted. When we say self-hosted, we really mean self-hosted: users are participating in the distribution of their content.
- We will consider this a gradient. We can analyze the system from the greatest extreme of centralization which can "scale towards" the greatest degree of decentralization.
- Finally, we will analyze both in terms of the load of a single participant on the network but also in terms of the amount of network traffic as a whole.
Okay. That is the structure we will use for our analysis. Let's compare "message passing" vs ATProto-style "global public shared heap".
So okay. Let's get the CS notation out of the way:
"Message passing" at full decentralization:
- O(1) from a single node's perspective
- O(n) from a whole-network zoom-out perspective (inherent: add a user, it's one more user)
Okay, that's reasonable and what you'd expect
"Public global no-missed-messages (or not worse than AP) shared-heap" ATProto style at full decentralization:
- O(n) from a single user's perspective (!)
- O(n^2) from a whole-network perspective (!!!!!!)
Oof I'd better back this up because that ain't good!
In other words, as our systems get more decentralized, message passing handles things fine. Individual nodes can participate in the network no matter how big it gets. The zoom-out for the network as a whole doesn't get more complicated as we add more users OR move more users towards self hosting.
Things are NOT good, if I'm correct above, as we make things more decentralized in the atproto-public-shared-heap model. The more self-hosting and indeed the more "full nodes" join, the more it gets expensive for each of the nodes and the network EXPLODES!
Truly self-hosted atproto is NOT POSSIBLE!
And there is no solution to this without adding directed message passing. Another way to say this is: to fix a system like ATProto to allow for self-hosting, you have to ultimately fundamentally change it to be a lot more like a system like ActivityPub!
Now I left more of the precise analytical explanation in my blogpost. But social media isn't great for that, so go check out my blogpost if you want to go through all that (eg if you're more like @dthompson and less like me, I'm a narrative person) https://dustycloud.org/blog/re-re-bluesky-decentralization/
Here's our story:
- We have 26 users: [Alice, Bob, Carol, ... Zack].
- Each user sends one message per day, which is intended to have one recipient. (This may sound unrealistic, but it's fine for modeling.)
- Each user sends a message in a ring: Alice => Bob, Bob => Carol, ... Zack => Alice
@cwebber @dthompson I was reading and reading your very interesting thread, and I was about to ask: "Can you put this into a blog post for future reference?".
Thanks!
@cwebber luckily no one will be self hosting /snark
@cwebber
I just wanted to say that I really appreciate your laying out this issue in simple terms...
@cwebber ok, so `n` nodes connect to `n-1` nodes each, O(n(n-1)) = O(n²), so quadratic is correct.
I think the thing about "gossip trees" is related to the tree structure which can be used to implement non-local multicasting.
stuff like https://en.wikipedia.org/wiki/Mbone is also interesting.