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I was thinking about how smartphones are very difficult to use in a way that does not transmit your location, with all the networks it has to connect to (and let's say a 'burner phone' is too expensive of a solution because of the prices of prepaid credit). I was thinking of a possible solution, I just don't know if it's possible, so I'm hoping someone here can inform me on the technical possibilities/pitfalls.

The idea

Let's say you have a server at home. When you're away from home your smartphone could potentially use any open wifi networks in the vicinity to establish a vpn connection to your home server.

When that is done, your home server would need to be able to receive phone calls in some way (maybe with some sort of bridge which bridges a landline to an ip phone on the network?), and then route any incoming calls to your smartphone over the vpn connection.

That way your smartphone would be able to receive phone calls over a vpn connection, and all incoming/outgoing calls would look like they're going to/coming from your home. Only the owner of the open wifi network you're connecting to, would know where you are (but that is a much more decentralized alternative to the centralized solution of always being connected to your mobile phone network).

Is it at all possible?

I know there are a lot of maybes, but can anyone inform me of the theoretical possibility of this idea? Would it be possible if the neccessary software were available? Can you improve upon the idea?

By the way

I know that there are apps that encrypt phone calls like redphone, silent circle etc, which make sure the contents of a phone call are relatively safe. What I'm trying to solve with this idea is how your location is always up for grabs because of your phone having to connect to a network of sorts. Even when you're using said apps.

A burner phone could solve the problem of hiding your location, but that is an expensive solution (prepaid credit is a lot more expensive). With my idea your phone could disconnect from all networks as soon as an open network is found, and connect to your home server.

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closed as primarily opinion-based by Adnan, NULLZ, Terry Chia, Noordung, Rook Aug 10 '13 at 17:18

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise.If this question can be reworded to fit the rules in the help center, please edit the question.

    
See question (and answers) of security.stackexchange.com/q/12659/5541 for a good explanation of the tracing part of the question. –  Marcel Aug 9 '13 at 21:46

2 Answers 2

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It's only marginally effective as it is still a) your number and b) your phone. If your cellphone is using data, it still has to connect to a local tower and that tower will give away your general area. The fact that the connection comes from your computer is irrelevant as it still is identifiable to you and your cellphone is identifiable to you. Putting two and two together would be relatively trivial, particularly if your phone's activity was already under surveillance.

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It is still your number. That's true, however let's say that the number at home being identified as mine is something I'm fine with, I just want to obscure my actual location by routing all my calls through my home landline. Like a proxy for my phone. The fact that the connection comes from your computer is irrelevant as it still is identifiable to you. The connection is still identifiable to me, that much is true, but the call would seem to be originating from the computer at home, and not from the smartphone I have with me, so my location would be much more difficult to trace. –  user7848 Aug 10 '13 at 9:24
    
It's only marginally effective as it is still your phone It is still my smartphone, that's true. But since it would not be connecting to any towers its location would not be traceable that way. The vpn connection over the open wifi network would be the only connection made by the smartphone. If your cellphone is using data It would not be connecting to a tower for data though. As I said it would be connecting to an open wifi network for that. So for all other connections it could be put in airplane mode, except for the one wifi connection. –  user7848 Aug 10 '13 at 9:25
    
The fact that the connection comes from your computer is irrelevant as it still is identifiable to you. To reiterate, this is not irrelevant, but actually very important. Because the origin of the call from my computer is what obscures my actual smartphones' location. I hope I've explained my question a little more clearly, and would like to read your response. –  user7848 Aug 10 '13 at 9:36
    
From the answer marcel linked to I could see that an IP PBX could bridge a landline to a voip phone. So something like this bit of software would be able to bridge an incoming call on a landline to a smartphone over a wifi connection. –  user7848 Aug 10 '13 at 9:37
    
@Samuel - they can trace your data connection of your cell. If someone was tracking you, they would be monitoring your cell phone anyway. You could have the call "appear" to come from home, but when they see your cell phone data connection is in a graveyard 500 miles away, they'll figure it out pretty quick. If you have it on wi-fi only then you would be a little better off, but no better than using any proxy. –  AJ Henderson Aug 11 '13 at 1:06

It's not possible this way. A (GSM) cell phone (re-)registers about every 15 minutes with the network, and also when there is a need for a cell change, even when there is no actual communication activity. Thus the location of the phone is trackable almost any time, when switched on.

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Hi, I've explained myself a little more clearly in the comments of the other answer. I'd appreciate your take on the matter. Thanks! –  user7848 Aug 10 '13 at 9:32
    
@Marcel - yeah, the key distinction is he did mention using open wifi briefly, I missed it too. –  AJ Henderson Aug 11 '13 at 1:16
    
OK, I think this boils down to the question from whom you want to hide/obfuscate your location. It will certainly not work for any agencies, not from your mobile carrier, and probably not from your boss when it's a company owned phone. But you have good chances it works for anyone not knowing your mobile phone number or not having the possibility to trace it. –  Marcel Aug 11 '13 at 21:08