-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 03/04/14 16:17, Ximin Luo wrote: > Could you go into some more detail on what you mean by delivery > receipt vs read receipt here? Under some interpretations, they > would be the same thing, just from the sender vs recipient points > of view.
A delivery receipt means the message has been delivered to the recipient's device; a read receipt means the recipient has read the message. WhatsApp and Telegram use a single tick for delivered and a double tick for read. I believe BBM uses S, D and R for sent, delivered and read. SMS can request delivery receipts, but not read receipts as far as I know, and I think it's optional to send a delivery receipt if one is requested. (Bernard?) As of a few minutes ago, Briar uses a single tick for delivered (for one-to-one messages only). I'm not planning to implement read receipts. > I can see how read receipts might seem creepy under some cases, > such as when demanded by someone you've never met, or when > immediately demanded over a high-latency medium. So, it's certainly > reasonable to give the user the option of not auto-acking received > messages.[1] Acks may be needed by the protocol, as they are in Briar for example. Whether the acks are shown in the sender's UI is a separate issue - but I tend to think that concealing something in the UI for privacy reasons when the information's present in the backend is a bad idea: it gives the user a false sense of what information is exposed to other users (who may not use the same UI). > However, the key point is that there is no way for a sender to be > certain about receipt until the receiver acknowledges it. If the > recipient purposefully withholds acknowledgement, then it is > reasonable (surely?[2]) for the sender to keep re-sending the > message until he gets the ack. Yes, I think that's what most reliable messaging protocols would do. > In a multiparty conversation, this is even more important for > transcript consistency - if Alice sends Bob a message M, Bob > cannot be sure that this was seen by Carol and Dave, until he gets > acks from them that refer to M. > > You probably still want to display the messages in the meantime > though, so I'm imagining a UI where some messages have an > indicator that "perhaps not everyone has seen this". But the UX > people will tell me if this would be too complex. ¬.¬ What 'delivered' and 'read' mean in a group context is a can of worms I haven't opened yet. :-) Cheers, Michael -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQEcBAEBCAAGBQJTPanQAAoJEBEET9GfxSfM0ywH/ij68YdjSSPbUOKoYUPHJhy5 oHixImMi+jzgm6uWLovPyIiBf6BKdiEnnxtPemkIQtHS/YF4OkWDFtjfERipcdGC 4ybcrO4CqxhdvRuddDdbnsFv60Sc/U+5XN1GmLfcvsynNQ9D2xAI77FkcTWkSzC2 ZLU30F5j9ei8vMqmpPd6PzkoE8mtR8jV1ehveyuoI554ojZJRJ4RbuNhzvsspEvD Ju1GYlbBCL0ckiiL6icow8pA4lVYgCIX6o6iPOmO6Nos8EWZoLdJn62WmIpsbduF yYwl+q4wIgGlwgo9N5HY7F6ZW4dkis/eM31RPZYyxjlaITV/JZNidz3ZGcW14SI= =twnO -----END PGP SIGNATURE----- _______________________________________________ Messaging mailing list [email protected] https://moderncrypto.org/mailman/listinfo/messaging
