Re: [Openbts-discuss] handover: same callID is checked by 2 transactions when HO is performed inside a cell

[Jet <icp...@gm...>]

Hi Dmitri,

I'll update the callid and fix for the coredump.
as for *the possibility of doing a separate procedure for handover  inside
a BTS, *I am afraid this might shift too far away from the current call
processing architecture.

Thanks,

Jet




On Wed, Aug 22, 2012 at 5:38 PM, Dmitri Soloviev <dm...@ma...> wrote:
> Hi Jet
>
> This letter is sent to a public list cause architectural aspects are
> discussed. Introduction can be found here
> http://wush.net/trac/rangepublic/wiki/Handover
>
>
> I've united your code with mine and tried to make handover work via SIP.
> Snapshot is git-ed
> https://github.com/dmisol/openbts-p2.8/commits/handover-sandbox The code
> added is not too nice, sorry..
> Transaction logic for incoming handover (air procedures) is more or less
> tested (HOCxxx-named procedures and HandoverEntry..)
>
> I tried to put your code into transaction for outgoing handover (I was
lazy
> to populated it properly, do not try to log it: logical channel is not
> initializes as it's useless here).
> While debugging, this transaction is living inside CLI thread.
> Core is dumped when HOcontroller() tries to read a SIP message and is
> surprised to find the incoming IVNITE that was recently sent from the same
> transaction 8)
>
> The problem is that when HO is inside a BTS, a single callID is checked by
> both outgoing and incoming handover transactions.
> So the question is: is it worth doing a separate procedure (that will live
> without SIP in between) for handover inside a BTS?
>
> Making CallID = "handover-<l3ti>-<imsi>-<last_ho_timestamp>" as desired
lets
> us
> - normally process a chain of handovers that loops back to initial site
> (it's timestamp will differ)
> - flip SIP loops (as IMSI is included)
> but we still have an obstacle when HO is performed inside a BTS (that
might
> be practically used when shifting timeslots for GPRS). And as for now, I
> have a single BTS at my disposal..
>
>
> Thks,
> Dmitri