one more thing that crossed my mind - it really depends on what you call a "silent sms", it may also be SMS sent to update some parameters of a SIM card (like (F)PLMN list), that is still a silent sms - most phones will not show anything about this being received .. and that will reach the SIM obviously.

however i have no knowledge what authorities/hackers actually use as a silent SMS.

2012/3/6 Harald Welte <laforge@gnumonks.org>
On Tue, Mar 06, 2012 at 09:06:22PM +0100, Florian Borggräfe wrote:

> i have a question about the functionality of the Osmoscon SimTrace
> hardware system.
> Can I log everything, also packets like silent SMS
> (https://en.wikipedia.org/wiki/SMS#Silent_SMS)?

I can only follow up to what Lukas wrote.  We can trace anything that
ever hits the ME - SIM interface.  But which phones might or might not
forward silent messages to the SIM remains an open question.

My personal educated guess would be that it is probably not sent to the
sim in the majority of the cases/phones.  SMS on the SIM is an ancient
relic, and then in the case of silent SMS, if the phone knows it shall
discard it, why first push it to the SIM...

Regards,
       Harald

--
- Harald Welte <laforge@gnumonks.org>           http://laforge.gnumonks.org/
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