Re: Help with silent call

Thanks Neel, it was of real help. BR ________________________________ From: Neels Hofmeyr <nhofmeyr(a)sysmocom.de> Sent: Monday, November 5, 2018 12:46:23 AM To: Snehasish Kar Cc: openbsc(a)lists.osmocom.org Subject: Re: Help with silent call On Sat, Nov 03, 2018 at 12:06:33PM +0000, Snehasish Kar wrote: Not listen to it in terms of audio. You can't eavesdrop on an MS with a slient call. You *can* open a channel and receive measurement reports from it, so that you see which other cells it sees at which receive levels, and how far it is from the current cell (TA). From that you could derive its position. The silent call has been one of the earliest features in Osmocom, but until recently has been broken in osmo-msc. IIUC it is now fixed again in current master, but might not be in a release yet. There's also the APDU a.k.a. the RR App Info (I hope I got the names right), which may or may not contain GPS positioning data that the MS is sending to the core net. In both cases the owner of the MS has no explicit idea that they are sharing any details on their position. ~N