[asterisk-dev] Proposal to seperate qualify & keep alive

[Johansson Olle E]

26 jun 2006 kl. 19.23 skrev John Lange:

> In the current implementation, qualify sends out a SIP request at the
> specified interval and if it doesn't receive a reply within that same
> interval asterisk flags the peer as unreachable.
>
> This also acts as a sort of keep-alive for devices behind NAT when
> combined with the nat=yes parameter. The regular flow of SIP packets
> keeps the NAT connective alive for the device behind the firewall.
>
> The problem is, these are two very different concepts and at times it
> would be nice if we could separate the two.
>
> Specifically; we have some clients with devices behind nat and
> satellite. Their nat and satellite requires a more-or-less constant  
> flow
> of packets to keep the connection alive.  However due to the quirky
> nature of satellite combined with long round-trip times the qualify
> option needs to be set high (5000ms) or Asterisk won't send calls  
> to the
> client.
>
> In fact we would like to set qualify=no because often the client  
> appears
> to be very lagged when the satellite perceives the connection to be  
> idle
> (apparently it queues packets until it has a bunch and sends them in
> groups) but if you initiate a call the lag drops immediately to an
> acceptable level (800ms).
>
> But if we set qualify=no then the firewall closes the connection and
> they can't receive any calls.
>
> So, the question is; is it reasonable to undertake the  
> implementation of
> a keep alive for sip clients?
>
> Any thoughts on how this should be done? SIP NOTIFY or would something
> else make more sense?

I don't see a reason for changing method. We should propably find a way
to override and be able to dial out regardless of the monitoring status.
That seems like a simple fix.

/O