Software Replacement of Mobile Phone SIM Cards
Original Publication Date: 2001-Dec-01
Included in the Prior Art Database: 2003-Jul-23
Mobile Phones in general have SIM (Subscriber Identity Module) cards for some functions. This small cards need to be handled carefully and have some limitations reagarding the storage and changing situations like the use of a new provider.
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Software Replacement of MobilePhone SIM Cards
Idee: Krisztian Rassay, HU-Budapest
Mobile Phones in general have SIM (SubscriberIdentity Module) cards for some functions. This smallcards need to be handled carefully and have somelimitations reagarding the storage and changingsituations like the use of a new provider.
SIM cards have some permanent information like thephone number, the provider code, network accessrights and more on it. In addition there is a memoryfunction for things like SMS storage and the phonebook. If someone changes his phone he has to removethe SIM card from the old phone to the new phone. Ifhe also changes the provider he has in addition to thatto get a new SIM card for his phone.
In general the permanent informations on a SIM cardcannot be overwritten.
Instead of this SIM card it is possible to use a puresoftware solution. By a secure data transfer protocolbetween the provider and the mobile phone it can besolved. For this it is necessary to use a privacymethod with private and public key pairs. So theprovider can assure the full and entitled access to therelevant settings of the phone.
Therefor it is necessary to create a key pair for en-crypting and decrypting to verify each side – theprovider and the user. The phone has to generate itsown private and public key which cannot be manipu-lated from outside.
To prevent an unauthorized intervention by crackingthe provider identifier keys and repr...