Exactly. I have never hard of silent SMS'es used for spying/tracking on people...

Silent SMS are the means used by both telephone network and police to track people. By the way, does N900 currently support Flash SMS?
Best wishes.

Thanks... was searching for it, but got a phone call distracting me.

Here's a working link:

http://en.wikipedia.org/wiki/Short_M...ice#Silent_SMS

That's exactly what 'silent SMS' stands for. Keep Alive pings. I want those exposed as silent SMS for tracking vary a little in their byte output from normal keep alive pings.

Even normal keep alive pings don't come as often as 'silent SMS' So any indication would be nice to at least know you're beeing tracked.

That's all I was asking for, if it's possible.

Cheers

actually, it's a feature of modem hardware, AFAIR. hw can choose to answer to some sms without even notifying the device.

That's what I'm asking. Does this go deep enough into the Baseband to keep track of what's happening on the old HW platform the N900 uses, or is it not going deep enough and we don't have a chance to see what's going on without open Baseband HW.

No, this does not go that deep. It's about daemon that works as a middleware between modem and higher level software, not about the modem itself.

Thank you for clarifying :-)

Quite a few ex-Nokians that worked on the N900 can be found on LinkedIn. A quick search yields some interesting results. Maybe some of these people will be willing help.

I would comment that attempts to avoid tracking are quite futile.
As Estel pointed out, there are "keep-alives".. those are actually called Location Updates (although their resolution is quite limited); there are data network versions called Routing Area Updates.
There are *many* other ways to know where your cell phone is, and it is a must. Else, the telco network wouldn't be able to ring your phone when a call comes in, or do other stuff.
I've also heard of methods called Geo-Location Tagging (probably won't appear on google) which is quite accurate.
SMS is only on the circuit switched network; the packet switched network, if your turn on your data connection, would open another circuit from your phone to the telco network, providing one more circuit that can be tracked from the operator network.

You can go look up signalling that happens between the phone & operator network under GSM, GPRS, 3G (HSPA), etc signalling.

The only way to be sure you are not tracked is to turn off your phone.

kh

And remove battery, as most nowadays devices (aka build in last 10 years, or even more) are able to power modem and allow "emergency tracking" even when turned off. I don't have idea how it looks in N900 case.

Thankfuly, the built-in bupbats aren't enough (yet) to allow tracking without real battery inside... Well, at least, not for prolonged time, so it's not implemented (or we don't know about it, yet )

/Estel

// Edit

Yes, it does. It comes up as pop-up notification (the black one, not yellow banner).