Re: [xmpp] 3921bis: probe + unavailable

[Peter Saint-Andre <[e-mail]>]

On 1/29/10 2:13 PM, Jonathan Schleifer wrote:
> Am 29.01.2010 um 15:58 schrieb Peter Saint-Andre:
> 
>> On 1/29/10 5:41 AM, Jonathan Schleifer wrote:
>>> Am 28.01.2010 um 22:40 schrieb Dave Cridland:
>>>
>>>> So a note's needed at minimum to explain that this didn't used to be a
>>>> requirement, and clients (and servers) SHOULD cope with no response as
>>>> meaning unavailable.
>>
>> The default is always unavailable. If you receive positive <presence/>
>> then you have some clue that the contact is online. If not, not. If you
>> receive a definitive answer that the contact is offline, that's even
>> better, but you can never assume that the contact is online.
>>
>>> The problem with that is: How do you figure out if you don't get a
>>> response or if you are just still waiting for it? We should define a
>>> sane timeout here, I guess, to prevent incompatibilities. This also
>>> means we need to figure out a sane value that even works with bad
>>> connections.
>>
>> I don't see a good reason to go down that path, which introduces more
>> complexity into clients.
> 
> So you suggest to assume all presences you already received as invalid
> when you send a presence probe and only take those into account that you
> got after the probe? Sounds like a solution, but a dirty one, IMO.
> 
> I think that sending back an unavailable a MUST is a good idea, as then
> you have a definite answer whether the user is online or not, whereas
> without, it could just be a laggy connection etc.

I suggested making it a MUST to return unavailable.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/