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Completely unaware of this social network. What problem, exactly, is a blockchain based social network trying to solve? Proof of origin? A conversational paper trail?

The latter would be interesting for areas where conversations should be on the record, however in cases that people want their conversations off the record they’d just use a side channel. The UK govt communicates using WhatsApp for Christ’s sake.

So it’d need to be something where both parties fundamentally benefit from the ability to verify that a post, or a conversation, took place. Where would that even apply?

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> What problem, exactly, is a blockchain based social network trying to solve? Proof of origin?

(SSB is blockchain in the strict sense, but there's no proof of work or anything like that. Each feed is its own append-only chain with its own private key.)

For SSB, the aim was to be able to gossip feeds via untrusted intermediaries, with patchy network connections all round, and be sure that the intermediaries haven't added, changed or removed any posts in the feed.

The protocol's designer lives on a boat in New Zealand, and other collaborators live in remote areas in different time zones.

One adjustment to the protocol that seems to me like a quick win (but presumably has some technical hitch I can't see, since I don't recall anyone suggesting this) would be to not include the post's body in the “block” (in the message itself that gets hashed and signed by the next message), but rather as a “blob” (essentially an attachment) which others don't need to download in order to verify the feed. That way old messages could be effectively forgotten if all peers co-operate (and no-one took a screenshot, etc).

> For SSB, the aim was to be able to gossip feeds via untrusted intermediaries, with patchy network connections all round, and be sure that the intermediaries haven't added, changed or removed any posts in the feed.

why would that need a blockchain (even without proof of work), as opposed to simple signed, timestamped, indexed posts and having the reading client app check the signature and post indices?

> > For SSB, the aim was to be able to gossip feeds via untrusted intermediaries, with patchy network connections all round, and be sure that the intermediaries haven't added, changed or removed any posts in the feed.

> why would that need a blockchain (even without proof of work), as opposed to simple signed, timestamped, indexed posts and having the reading client app check the signature and post indices?

It depends on how the message is signed. If the message format's this:

sign_message(message + timestamp + index) + message + timestamp + index

The 'index' can be manipulated: The signer (malicious or not) can resign an old message & effectively overwrite a previous message.

sign_message(new_message + old_timestamp + old_index) + new_message + old_timestamp + old_index

This means that in the event of such a resigning, it's the app's responsibility to prevent resigned messages from overwriting old messages.

Blockchains prevent this at the data structure level because signature hashes are effectively random, meaning they're near-impossible to tamper with:

whole_message := prev_message_hash + sign_message(message + timestamp) + message + timestamp

wherein prev_message_hash := hash(prev_whole_message)

Just as a reminder: The original stated task was to protect against "untrusted intermediaries" and "patchy network connections", and in particular to make "sure that the *intermediaries* haven't added, changed or removed any posts in the feed." … which can perfectly well be done with simple signed, timestamped, indexed posts and having the reading client app check the signature and post indices.

In contrast, this here, which is the only thing the blockchain struckture really adds:

> The signer (malicious or not) can resign an old message & effectively overwrite a previous message

… is a rather radical shift of the goalpost, as the only capability the blockchain really adds is to protect against modification not by untrusted intermediaries (which was the purpose and which would already be covered without a blockchain) but by the legitimate owner/editor of the feed.

In other words: The only thing the blockchain adds is that it makes it impossible for YOU as the user to edit YOUR OWN posts. I'm not sure that's something most people in the social network context (as opposed to, say, a financial transaction ledger) would see as a feature and not an anti-feature.

> why would that need a blockchain (even without proof of work), as opposed to simple signed, timestamped, indexed posts and having the reading client app check the signature and post indices?

Yeah, that's exactly what SSB does, plus each post includes a hash of the previous post.

I think that's so that even the holder of the private key can't retroactively replace an old post with an altered version of that post (but with the same index number and similar timestamp).

Why do you need social network non-repudiation again? These are the programs over which people shitpost... Correct?

Feels like people are really just trying to play into "everyone has a number that can be banned" for the Internet/social life in general.

> One adjustment to the protocol that seems to me like a quick win (but presumably has some technical hitch I can't see, since I don't recall anyone suggesting this) would be to not include the post's body in the “block” (in the message itself that gets hashed and signed by the next message), but rather as a “blob” (essentially an attachment) which others don't need to download in order to verify the feed.

There's nothing to prevent you from taking this route, you just sign a blob hash instead of an entire message object.

I work on an experimental SSB-like-protocol in my spare time that does exactly what you've suggested: https://github.com/evbogue/bogbook

I don't know if this makes the network forget more, but the aim is to reduce the time it takes to sync and get started.

I'm working on something in this space, though god knows if I'll ever finish it. And that's one of two approaches I considered to that problem. Another is to have a signed deletion marker saying something to the effect of "there was a block here with hash d9841a, but now there isn't anymore, and I'm its replacement".

> What problem, exactly, is a blockchain based social network trying to solve?

I think the problem it's trying to solve is: "How can we mix social networking with blockchain?"

To my understanding, it allows messages on the network to have a total order, even when fully decentralised. Without a hash chain, clients could not tell what order events happened in, and might display them ordered differently, which would change a conversation's meaning.

The traditional alternative is logical clocks, but a malicious participant could forge those, so they're not suitable for a fully distributed system run by random users.

AFAIK it was intended to support the use case of being occasionally connected to the internet (one author spent a lot of time on a small sailboat in the south Pacific), while maintaining an order of messages.

Lotus Notes solved that problem over 30 years ago.

And newsgroups, email, uucp etc.

> Where would that even apply?

That sounds like it could be useful in legal and policing contexts. One complaint I’ve often heard about body cameras in policing is the possibility of footage that was created and did indeed exist being “lost”, with the implication being that legal entities intentionally destroyed evidence of either the footage existing, or its contents.

To the extent that this centralized authority issue applies to textual data or metadata, decentralized records of messaging times and contents would potentially be an invaluable tool of transparency and promoting systemic confidence in a visible shared audit trail.

> What problem, exactly, is a blockchain based social network trying to solve?

The same as every other blockchain application: the problem that no-one has found a practical use for Blockchain despite 14 years of effort, but that blockchainers continually need the next wave of hype so that their coins don't lose value.

It's about as much blockchain as git is blockchain, so... not really blockchain at all...

Maybe betting? Both sides are usually interested in recording the bet.

> What problem, exactly, is a blockchain based social network trying to solve? Proof of origin? A conversational paper trail?

I would say the main interesting problem to solve is how to have a social network with a shared state without requiring a all-powerful central party like the existing solutions. Blockchain solutions allow a consensus about what is in the network without this.

If you don't care about the social network state diverging endlessly that's not a problem, but part of the "social" part of social networking is that users expect to see broadly the same messages or at least that all messages are drawing from a common well in the sense that I can choose not to follow a particular person or conversation, but if I do follow them/it then I see the same set of messages as others who are following. This is how we have a shared conversation.

Edit: Not saying this is the only or best way to do this, but it is one way and I believe this to be the problem blockchain social networks are trying to solve. eg these guys are building a blockchain social network and it's explicitly one of their goals https://www.projectliberty.io/

> What problem, exactly, is a blockchain based social network trying to solve?

The problem of justifying the existence of blockchains.

Same problem every problem using blockchain tries to solve.

Getting funded by people thinking it will be next big thing.

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