Re: Multiple SIM cards for N900
 

It does sound like a reasonable proposal but -

I've worked with smart (credit) cards before, and it's entirely possible that there are challenge/response situations where secret keys are used, within the SIM card, to generate data to authenticate with the network.

I would be very surprised if you could just dump the data off the card and use it in the way you propose.

It's still agood idea and worth investigating, but don't be too disappointed if it won't work.

With that said, I'd be interested to read more about the mulit-sim cards mentioned by the other poster above.

Also, does anyone know if the multi-SIM phones require multiple radios?

Re: Multiple SIM cards for N900
 

I have seen these phones when I was back on my home town:
1. 2 CDMA sim card active at the same time
or 2 GSM sim card active at the same time
or 1 CDMA and 1 GSM active at the same time.

Catch: These phones typically getting hot faster when its being used.

I dont think I would like to see SIM Card using an image, I can imagine that can be used for fraud.

Re: Multiple SIM cards for N900
 

Oh sure, I've seen multi-sim phones for sale, was just wondering how they worked and if they need multiple GSM radio chips or what.

As I say, I'd be really surprised if software enulation would work precisely for the reason you mention - it would be a big fraud risk and I know other SIM style chips (smart credit cards) have protections against that sort of thing.

Re: Multiple SIM cards for N900
 

that would be nice to have both att and tmo sim in at time to use att for phone service and tmo for 3g

Re: Multiple SIM cards for N900
 

Wouldn't this invite the ability to put copies of SIM cards on torrent sites or whatever. People could just download random SIM's at will and use them. Sounds evil to me.

Re: Multiple SIM cards for N900
 

You can put your credit card info in a .txt file too, but nobody seems to be too concerned...

Being able to rip sim cards and use images of them in the software would be awesome, but I doubt it's possible. Reading and using the SIM is a hardware/firmware-level thing AFAIK.

Re: Multiple SIM cards for N900
 

would something like this work ?

Re: Multiple SIM cards for N900
 

Have you ever heard of redirect? That at least skips the incoming call problem. Does the N900 gsm chip support dual lines/numbers (single SIM)? If yes does the software support it? If no, is a bugreport/enhancement request open?

There are several ways to have a look at this! One is to buy a china forked n900 with compass and dual SIM card slot but I doubt it that you ever run maemoX or MerY on it.

The problem is to have the GSM run SIMs software based wont work afaik (hardwired).

Re: [Proposal pending] Virtual SIM cards for N900
 

One possible avenue for faking in alternative SIMs would be SAP -- AFAIK the N900 doesn't support SAP, but its existence makes it reasonable that the closed cellular code could permit SIM access other than through the physical socket...

Of course, that doesn't simply allow virtualizing a SIM; the ultimate goal here would require breaking the challenge/response authentication system to extract the SIM's internal key. AIUI, this is the same issue as SIM cloning, which is generally possible in reasonable time on really old SIMs, but not on recent ones (due to now-fixed weaknesses).

Re: [Proposal pending] Virtual SIM cards for N900
 

i can confirm the above. i've cloned a fairly few simcards long ago in the past ( it was nice little earner - i had a lot of customers wanting a cloned sim to use the same number in their car phone. some of you may remember those big handsets on a cable built into armrests in cars)
.
anyway - since the fix to KO security key on simcard was introduced it is almost imposible to clone the sim. i mean you can copy almost entire sim but without the KO key you will not be able to use it in any phone. sorry

as to double sim "N900" from china - first of all - this horrid thing is not even close to real N900 and you can forget running maemo on it. also all of this double sim phones you can see on ebay have 2 radio modules one for each sim.