On Wednesday 30 September 2009 13:23:10 Harald Welte wrote:

Hi Zecke,

I've been reviewing some of your patches:

...

commit 45f9b3d3fc47074652be951eb74df2b0be2a230f Author: Holger Hans Peter Freyther zecke@selfish.org Date: Fri Aug 21 05:30:19 2009 +0200

[paging] Use one of the two reserved LAC to page every BTS

For the on-waves.com MSC case we want to page every BTS reached
of the network. Our gsm_subscriber entry does not have a LAC
entry set and defaults to zero. Use the reserved 0x0000 to
indicate that we want to use every bts in the network.

This will influence the paging code to start and stop paging.

The problem is that in the current code, we use LAC == 0 to indicate that the subscriber has sent an IMSI DETACH message, i.e. switched his phone off.

You are now redefiniing the LAC 0 to something like the opposite case, which I don't particularly like. Is there some alternative solution?

I didn't think about the IMSI DETACH case. One easy alternative is to use the other reserved lac value. With the least significant bit set 0 and all others to 1 (so 0xfffe... ETSI always makes me unsure about it).

The other option is changing gst_bts_by_lac to specify to not filter by lac but just give the next one.

what do you think? z.