Nokia InSite handover

[Sipos Csaba]

Hi Harald,

> Hi,

> On Mon, Jul 08, 2013 at 09:19:23PM +0200, Sipos Csaba wrote:
>> I got a strange error message, that I have to enable RTP Proxy
>> mode with "-P" in osmo-nitb. 

> That's of course funny.

> Please take some minutes of your time to look at the source code line
> that generates yoru error message.  I'm sure (without looking) that
> the message will be printed if bts->model != SIEMENS_BS11.  So you
> simply need to extend that to include all E1 based bts's.

The part generates this message is the following:

openbsc/openbsc/src/libbsc/bsc_vty.c

#define HANDOVER_STR    "Handover Options\n"

DEFUN(cfg_net_handover, cfg_net_handover_cmd,
      "handover (0|1)",
        HANDOVER_STR
        "Don't perform in-call handover\n"
        "Perform in-call handover\n")
{
        int enable = atoi(argv[0]);
        struct gsm_network *gsmnet = gsmnet_from_vty(vty);

        if (enable && ipacc_rtp_direct) {
                vty_out(vty, "%% Cannot enable handover unless RTP Proxy mode "
                        "is enabled by using the -P command line option%s",
                        VTY_NEWLINE);
                return CMD_WARNING;
        }
        gsmnet->handover.active = enable;

        return CMD_SUCCESS;
}

After I removed this check, I was able to start OpenBSC with
handover=1, even the OpenBSC VTY said to "show network" that handover
is On, but I was not able to do any handovers even when there was
30-40dB difference (RXlev) between the target and the source cell. The
target was ate -50, the source was around -100, suddenly the phone
jumped to the target cell, but after 3-4 seconds of terrible noise,
both phones are dropped the call. I think it was a cell reselection
not a failed handover, because there was no HO attempts in the
statistics.

>> Because these units are running from E1, I just simply ask: do we have
>> handover support for E1 based BTSs? 

> yes, this was already working with the BS-11 a long time ago.


If I can help resolve this issue, just let me know what to try.

BR,
Csaba