On Tue, Nov 3, 2009 at 7:59 AM, Peter Saint-Andre <[email protected]> wrote: > > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 11/2/09 11:18 AM, Dan Peterson wrote: > >> * Reliable Delivery: >> o For any communication mechanism it is important that there >> is a contract for delivery of the message contents, and we >> are working on a reliable delivery mechanism >> from WaveSandbox.com. > > What is meant by "reliable delivery"? What are your requirements for a > reliable delivery mechanism? I ask because the broader XMPP developer > community has put a lot of thought into this problem, and depending on > your needs a solution might already exist. Let's not reinvent the wheel > if we don't need to. :) > > Peter
Hi Peter, We're still working through some of the finer points on "reliable delivery", we're also hoping to incorporate some form of flow control. We have yet to write a full spec of how we envision this mechanism to work, so if you allow be to be brief, we expect the requirements for "reliable delivery" to be: - short term retransmission and acknowledgement of all messages (this can be done using regular XMPP mechanisms). - selectively dropping non-essential messages queued for retransmission if there are any non-trivial transmission delays (e.g. delta updates, which can be recovered by a receiver using getHistory on receipt of a commit notification). - keeping retransmission efficient by only sending of essential messages over a significant amount of time (e.g. days, weeks,.... months? if a wave provider has gone offline. The retransmission policy might be similar to what happens with SMTP (*)). Essential messages would include the last commit notification for all wavelets on which a provider has users. (*) One might possibly add an active mechanism on the receiver's part to query for new waves, however there are a few issues with this. e.g after being down for a long while, receivers can't know the complete set of servers to contact for waves without some central authority informing a provider which providers have waves for whom. regards, Jochen --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Wave Protocol" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/wave-protocol?hl=en -~----------~----~----~----~------~----~------~--~---
