Tuesday, November 18, 2008

Ultra-thin membrane changes (U)SIM card usage

Ultra-thin membrane changes SIM card usage

Examiners may come across an ultra-thin (0.3mm) membrane that lays over the contacts of a SIM card. Called the V200 SIM Dialer, the membrane is "Prefix base programmable (For routing prefix and bypass prefix setting)". What does that mean? Well, it allows mobile phones installed with SIM Tool Kit menu (most up to date phones have them) and define access to the network. The point being, if you are looking for least-cost routing for calls or want to use a calling card, rather than have mobile network call charges, then this device makes that happen, apparently.

How does it do it? "Dial the desired number directly each time you call, SIM dialer V200 will automatically dial IP access in front of the dialed number".
As the manufacturer promotes, using their device will not change your dialling habits and there is "No cutting, No pounching your SIM".

As the device has been programmed, and looking at the on-board chip, there should be a reader for it or one could be constructed. This throws me back to the old days of ponyprog and PIC basics. Of course, of equal importance is how does this device impact when examining the handset and SIM card? Will manual examination be the only course for examination or do the current handset and SIM readers detect changes this device makes to them? What evidence is there for call history or data usage? These are just a few of the questions to get examiners started.


It seems this programmable ultra-thin membrane is not limited to just SIM calls, but there is a USIM version (U-SIM V33G) that can be used to unlock iPhones. There is a video that is useful to watch so that examiners can at least comprehend how ultra-thin the membrane is and how it is installed:-
http://tw.youtube.com/watch?v=JQSNJxis7Ds



Please note, this is not a promotion or advert for these products, the information provided is to assist examiners with observations about these devices that may form part of their evidence.