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ActivityPub: decentralized social networking protocol

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Re: ActivityPub: decentralized social networking protocol

#11

Post by jeswin »

detaro wrote: post #9
jeswin wrote: post #7

From my quick read of the spec, server-to-server federation assumes that servers can be trusted. That need not be the case; unless a message is signed it should not be assumed to have come from a specific user. I don't know if there's an easy way to share keys in a decentralized way, but that'd be an interesting problem to solve (some blockchain maybe). The other question is whether we want server-to-server federatio…

That need not to be the case, but realistically it is the case for Mastodon & co for now. People are looking into various signature schemes, potentially as extensions of the protocol, but it would have moved the entire thing into very untested waters, which is bad for a new standard. Same with federation: It's what you need right now for "normal" users (e.g. compare user numbers of Mastodon etc to purely p2p alternat…

As a counter example, there are millions of non-technical users using the bittorrent protocol. They are running a server on their machines and not aware of the technical complexity that lies underneath. I am not saying it's an easy UX problem to solve, but it can be done.

Re: ActivityPub: decentralized social networking protocol

#14

Post by carussell »

kemenaran wrote: post #5

This protocol is a successor to OStatus (GNU Social), and mostly made by the same people. From what I remember, Mastodon switched from OStatus to ActivityPub a few releases ago. In the past they had to extend the OStatus protocol for private messages, which meant some clients may not honor the private status of theses posts. ActivityPub has private messages defined properly in the spec. It seems PeerTube ( https://gi…

Last summer I tried untangling the OStatus/pump.io/ActivityPub/ActivityStreams nest hoping to piece together a big picture mental image based mostly on what Wikipedia has to say, and found it mostly frustrating.

For anyone who's similarly curious or confused, LWN published a pretty great overview last month—their "Federation in social networks" article:

https://lwn.net/Articles/741218/

Re: ActivityPub: decentralized social networking protocol

#16

Post by AsyncAwait »

jeswin wrote: post #11
detaro wrote: post #9

Earlier quoted context omitted.

That need not to be the case, but realistically it is the case for Mastodon & co for now. People are looking into various signature schemes, potentially as extensions of the protocol, but it would have moved the entire thing into very untested waters, which is bad for a new standard. Same with federation: It's what you need right now for "normal" users (e.g. compare user numbers of Mastodon etc to purely p2p alternat…

As a counter example, there are millions of non-technical users using the bittorrent protocol. They are running a server on their machines and not aware of the technical complexity that lies underneath. I am not saying it's an easy UX problem to solve, but it can be done.

Sure, I think the problem with people running i.e. Mastodon on their own machine would be what should happen when people turn off their computer.

I guess there could be some sort of "super node" solution, where a known Mastodon server would just forward you the "what happened while I was asleep" stuff and I guess people could encrypt their messages to you with your advertised public key, so that you don't have to trust the super nodes, but I am not sure about the additional complexity involved in implementing that vs current Mastodon using ActivityPub, nor about the usability challenges involved.

Re: ActivityPub: decentralized social networking protocol

#17

Post by rakoo »

jeswin wrote: post #7

From my quick read of the spec, server-to-server federation assumes that servers can be trusted. That need not be the case; unless a message is signed it should not be assumed to have come from a specific user. I don't know if there's an easy way to share keys in a decentralized way, but that'd be an interesting problem to solve (some blockchain maybe). The other question is whether we want server-to-server federatio…

> I don't know if there's an easy way to share keys in a decentralized way, but that'd be an interesting problem to solve (some blockchain maybe).

This is exactly what namecoin tried to solve. Buy an identifier, put whatever you want in it. Example: https://nameid.org/?name=rakoo

> The other question is whether we want server-to-server federation at all instead of a P2P network like bittorrent.

We want something in between. The best model I know is the one of scuttlebutt (http://scuttlebot.io/more/protocols/secure-scuttlebutt.html): Each peer is identified by an asymetric keypair, and writes posts/comments/photos to a local ledger. Everything is signed and potentially encrypted if the message is to be read only by select people. Diffusion follows the peers' connections: stuff is sent from peer to peer as they connect together, friends can be used as a third leg (ie a common friend can carry stuff even if it's not for them), and you also have pubs where more people can connect and get more stuff faster. This system is different from bittorrent in that everything depends on the human connections: information spreads along human acquaintances, names aren't globally unique, they depend on how your friends agree to name you, etc...

It's better than naive server-to-server federation because pubs can be simple, stupid message forwarders yet still have all the advantages of being always-up servers.

Re: ActivityPub: decentralized social networking protocol

#18

Post by rogerbraun »

kemenaran wrote: post #5

This protocol is a successor to OStatus (GNU Social), and mostly made by the same people. From what I remember, Mastodon switched from OStatus to ActivityPub a few releases ago. In the past they had to extend the OStatus protocol for private messages, which meant some clients may not honor the private status of theses posts. ActivityPub has private messages defined properly in the spec. It seems PeerTube ( https://gi…

Privacy on the level of AP would have been very easy to add, by just using a different salmon endpoint for private messages. This was discussed at length back then, but Mastodon still chose to implement the leaky-by-default changes. There's nothing in AP that can't be done using OStatus, with very very minor extensions.

Re: ActivityPub: decentralized social networking protocol

#19

Post by JepZ »

eeZah7Ux wrote: post #13
freeduck wrote: post #3

ELI5 ActivityPub vs xmpp semantics

AFAIK XMPP is more geared towards IM than microblogging and it's very complex and difficult to get right due to many extensions.

Actually, I never did any XMPP coding but from what I belief it is more difficult to get it 'complete' then to get it 'right'. I mean you get it 'right' even with a minimal/core implementation but 'complete' only with about the 50 most common extensions. Getting it 'right' seems to be a problem when the XEP definition is open to interpretation.

Nevertheless, I agree that it would not fit the XMPP ecosystem to be used as a micro blogging service. It's like using e-mail for IM: Possible, but not recommended.

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