Hi Have spent the last few weeks going through various web pages describing GSM cloning. Some contradicting views, but overall the point is well made (and quite correctly) - cloning and/interception/monitering is both viable and achieveable. I recently was commissioned to look into this subject on behalf of a client who wished to moniter a GSM phone. Putting aside the rights and wrongs of the issue, we realised the objective. In summary it is possible to moniter/intercept a GSM phone using 2 pieces of commercially avaliable RACAL equipment, linked via a custom made preselector/combiner. The overall setup is easily portable and is controlled via a pc. It goes without saying that RACAL do not market the hardware for the above purpose - it has legitimate engineering needs, and is marketed under that legimate need. RACAL do not make the precombiner/selector (we had to make that) and they do not market the software AT ALL. I suspect that they are aware that the hardware in conjunction with the software (and access to a combiner/spliter)would give access to interception. So you must be thinking what sim parameters (or other parameters) had to be programmed into the pc software programme to allow selective interception of a GSM phone? Very little - in fact all that had to be programmed in was the phone number of the GSM handset to be targeted - and absolutely nothing else! It's food for thought. Best Regards Patrick_33@hotmail.com *This is not for general distribution on the web, but is shared with you on the basis of what appears to be a serious discussion on the subject on your side. please respect that aspect of confidentuality and feel free to get back to me with any comments you may have. One important aspect of the exercise has been deliberatly left out, it has little effect on sizing or costing but none-the-less is a requirement. Most engineers who understand what is involved in running 2 pieces of rf equipment in parrallel (both in TX and RX functions)at the same time will understand what is left out. ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com