[OpenSIPS-Devel] [presence] 'expires_offset' also for NOTIFY ('notify_expires_offset')

[Anca Vamanu]

Hi,

The expires_offset is somehow supposed to do that - but it lost the 
initial meaning in the mean time :) .
I will fix that.

Thanks,
Anca


Iñaki Baz Castillo wrote:
> Hi, I've detected an issue related to NOTIFY "expires" value when
> there are retransmissions for the NOTIFY sent by OpenSIPS:
>
> Imagine that a OpenSIPS sends a NOTIFY "expires=30" to a client at 12:00:00.
> Due to some reasons, the client doesn't reply to it (or perhaps there
> are network errors) so the NOTIFY is retransmitted by OpenSIPS.
> Finally the NOTIFY arrives to the client at 12:00:01.
>
> If the client is too strict, it will send a refresh SUBSCRIBE at
> 12:00:31, so the subscription has expired in the server one second
> ago.
> This will cause a "481".
>
> Unfortunatelly some clients (as Qutecom) work in this way, and the
> worst: they don't react well when receiving a 481.
>
> So I suggest a new option "notify_expires_offset":
>
>   modparam("presence", "notify_expires_offset", 5)
>
> In the above case (with retransmissions) it means that the client
> would receive a NOTIFY with "expires=25" at 12:00:01, and the client
> will send the refresh SUSBCRIBE at 12:00:26 (before 12:00:30, the time
> in which the subscription would expire in the server), so it would
> mitigate the 481 issue.
>
> Is it feasible to add this option? opinions?
>
> Thanks a lot.
>
>