Hi Dan

On Thu, Nov 19, 2009 at 10:47 AM, Daniel Paull <[email protected]> wrote:

>
> hi Ben,
>
> Thank you for the link to the patch.  I will certainly have a look at
> this.  Can you elaborate on what problems were found when not using
> the server acknowledgement (is there a discussion thread somewhere on
> this?  I couldn't find one.)
>
>
In the case of FedOne, this was causing a problem when Echoey was added to a
wave with a user on wavesandbox.  Unlike prior FedOne usage, these deltas
come very quickly due to the real time character transmission.  Echoey was
replying to deltas without the response coming back, such that its echoed
deltas were being submitted at the wrong version (confusing FedOne and
corrupting the wave).

(This is actually part of a different patch I was working on which fixed
Echoey to work with wavesandbox.  Once this patch is submitted, I'll put the
other out for review too).



> One thing that is not clear from the Google Wave white paper on OT is
> when acknowledgements are sent from the server to the client.  What
> I'd like to determine is if operations are sent from a number of
> clients to the server concurrently, or, does the server make clients
> take turns in sending operations to the server.  Though I haven't done
> the math yet, I would expect that if clients send operations
> concurrently to the server and the server maintains only a single
> state space, then the OT transformation functions would need to
> satisfy TP2 (which is avoided in the Jupiter system).  If I'm not
> right here, are there any resources around that formally prove
> correctness in the OT approach of Wave that I can read?
>
>
I am not an expert on OT so I can't answer the second part of the question,
but as to the first, yes clients are permitted (you might even say
encouraged) to submit concurrently to the server.

(There is of course concurrency control inside the wave server to prevent
race conditions arising from this...)

-- Ben

--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---

Reply via email to