I need to factory unlock my iphone4s running on ios6

Currently the only way to unlock your iPhone 4S would be to do it officially via your carrier. There is no hack unlock for iOS 6.0 at the moment and with the new DCMA ruling this isn't likely to change for any newer phones.

Hi instead of using factory unlock service to unlock your iphone4s. You can unlock it use remote unlocking method. Which is the safe and secure method to unlock iPhone. You can get this service from ProUnlocking.com here you need to specify your country, Network name to which it is locked, IMEI number of your iPhone. Here they unlock your iPhone using latest versions of iTunes. This is permanent unlocking solution. Both upgrading and downgrading will not lock your iPhone again.