How does an operator control access to 3G services on 2G GSM SIM?

[Yasmin]

Hi,

I would like to know how a network operator can control whether their 2G SIMs are able to access a 3G network? I've been told on this forum and have also heard that 2G SIMs can provide the same experience as a 3G SIM if the handset and network are 3G AND the network operator provides access to it. How does the operator control this?

I would appreciate ANY help I can get on this. Thanks!

[mrubs]

SIM doesn't matter. It works with the network & Devices

[bsrjl1]

When the PLMN is defined in the MSC, it can set minimum ciphering requirements. If they require KASUMI then a '2G' SIM won't work.