Open protocols and federation are cool and all, but XMPP is not the protocol that will let someone be competitive in this space.
(Disclaimer: I work at Google. This is my opinion. I do not work on Hangouts.)
Examples:
- unique message IDs? Absent. XEPs kind of provide; but I can't tell you which of the three or for relevant ones are the most relevant (AMP IDs from XEP 0079? Stream Management from XEP 0198? Acking from XEP 0184? Something from Carbons or MAM in 0313 or 0280? You know, if you wanted some light reading...).
- multi device? Oh. My. God. It's bananas. The spec behavior is that whenever a client sends a message, the server is supposed to consider that one the most alive, and then route all future messages exclusively to that one. So you send a message on your phone? Yeah, your desktop is just going to silently stop receiving messages.
- there's a concept of "message carbons" to deal with this. This involves re-sending all your messages back to the server after you receive them, with special instructions to send them back again to your other clients. The amount of redundantly redundant XML involved is eyewatering.
Combine that multidevice behavior (messages can get randomly routed anywhere at any time) with the wild-west nature of message delivery acks, and you can see how ridiculously difficult this makes the basic idea of "all clients should see the same picture".
Overall, the XEP process, conceptually, is a great example of open extensibility. The trouble is, so much of this stuff is core to sane message delivery semantics that it really, practically speaking, causes huge problems when it's all considered "extensions". Stuff like message IDs fundamentally shouldn't be an extension because it's just too critical that all minimum-viable clients agree. You just can't build higher level stuff without that. XEPs are great. A community process for extensions should exist. It just needs to exist for extensions, not subsume the total set of realistic minimum viable features.
I want an open chat protocol.
I thought XMPP might be the one. Then, as the parent comment jibes, I actually looked at it. Tried to write something with it.
XMPP is not prepared to be the one, in any sense at all except for legacy support. I have all the respect in the world for all the folks who put effort into trying to make an open chat standard, but... honestly, we need a stronger foundation than this.
What I'd like to see is a messaging system that gets the basics right, and that's deeply aware that it's AP out of CAP. Messages are inherently commutative (think CRDTs) and can be received in arbitrary order; people on two sides of a partition should have no trouble reconciling coherent logs regardless of if there was a two minute netsplit or someone was backpacking for two weeks. I'm looking for any existing stuff that suits this, and willing to collaborate on making it if it needs to be made!
It looks like they did tackle acausality head-on; I like what I see about previous message IDs being included in https://matrix.org/docs/spec/#pdus
Nervous about ever christening JSON "today's technology". JSON has the same problem XML in XMPP does: can't tunnel binary e.g. video without extreme backbending (jingle for XMPP is pretty much a textbook example of "too much friction -> not fit for purpose and near zero adoption"). But it looks like matrix is pluggable on transports, too, so that's potentially a sweet spot for lazy REST clients and powerful performance situations to coexist.
... And I popped into their self-hosted chat room. Observation 1: It works (!). Observation 2: the devs are dogfooding and seem both knowledgeable and friendly :) I haven't taken the leap to self-host yet (will later!); but from preliminaries, matrix is looking remarkably solid and well thought out. I'm going to try to build something with this! Thanks again for the link!
I use this to say "XML was the hot when XMPP was created, the way JSON is the hot today, when Matrix is created". I 100% agree with you that using a non-binary-friendly format sucks for pretty much anything that goes beyond plain text messaging:
- encryption
- files/emoticons/voice
- on the server side, any routing stuff
But still, like XMPP I hope this will not be enough to hamper its development.
> jingle for XMPP is pretty much a textbook example of "too much friction -> not fit for purpose and near zero adoption"
Amen to that. XMPP is basically an entity-to-entity messaging protocol, and yet because it can't handle binary there needs to be a negotiation step and yet another connection for binary stuff... blah.
The server-server API is currently just targetting https+json just for expedience in getting started, but nothing to stop us negotiating more efficient transports in future - capn proto has come up a lot in conversation as a possible option. Handling signing is a bit more fun as we currently rely on signing canonical json, but surmountable.
As for binary transfers... well, random blobs are just handled as pure HTTP with a mimetype currently :)
I'll be honest with you my friend. I would prefer to physically mail people coins then use facebook/google/apple pay. As much as I distrust banks, they at least have a record of letting me move to a competitor if I ask.
Then create an open protocol that supports what the users want
If Facebook valued compatibility with as many different products as possible, then they would keep XMPP support. The issue is not about features or XML. Most likely, it's about them wanting full control over the end-user experience: "We recommend people access Facebook Messages on the desktop via Facebook.com or Messenger.com."
Perhaps it is about providing the right hooks into the specification to not compromise the end user experience.
I think Docker is an interesting project to follow in this regard. They have shown the ability to get both startups and large players (amazon, google, microsoft) onboard by keeping the platform open. Yet they are clearly focused on providing the best experience for developer/ops interaction with cloud services. It will be interesting to see the rollout of their extension mechanisms and whether they can be a primary interface to cloud services or will become a second-teir compatibility layer. However, even in this case perhaps chat protocols could learn something here.
Because otherwise you end up with design-by-committee.
An interesting example is Google with SPDY. They wanted something new, built it, tested it, and then wrote the specifications (along with other actors of course). I think it is fair to say that without the SPDY experiment we wouldn't have seen HTTP/2 coming so fast. Google and the other actors had enough incentive (and actual time and money to spend) to make it go further. In the case of XMPP there's no such actor, unfortunately.
Its not broken. Standards are, ideally, distillations and applications of proven experience in a generally applicable way. You don't want standards trying to ride the bleeding edge, they want them to apply what is proven.
(OTOH, its good to have those working on the bleeding edge also opening for discussion how those experiments might be standardized while the experiments are still ongoing, and one vehicle for those discussions is draft standards or draft updates to existing standards.)
Photos: No problem with XMPP. Just inline them if you want.
Voice calls, video calls: Easily done with Jingle, which is a XMPP standard.
Stickers: See above, they are just a special form of smilies which like any client supports.
And so much more: http://xmpp.org/xmpp-protocols/xmpp-extensions/
I wonder if you know what Whatsapp is based on.
Could you cite at least 1 client that does all of the above on each platform (Linux, Windows, Mac OS, WP, Android, iOS) ? (This is a genuine question, I'd like to know if it really is possible, especially on mobile)
It is no surprise that Whatsapp and the like are so successful. Textsecure/Signal is being too slow, I am afraid they missed their window of opportunity for fast widespread adoption.
Why not work on pushing an open standard instead of locking users into your proprietary client? I already know the answer (ads and user data collection; see also: G+), it just leaves a bad taste in my mouth #dontBeEvil
File transfers, nothing new here.
> "videos"
Either file transfer, or live voice+video. Neither are new. I last used XMPP+voice+video about five years ago.
> "stickers"
Image transfers. Or custom emoticons with a large size. Again, nothing new.
> "Western Union"
???
> "voice calls"
Again, nothing new about this.