When you know that your interlocutor is a Minor, you are legally responsible for what you show/say to him/her. In the past and in the present people who offend, molest or ravish a Minor could prove to not know that the victim is a Minor. With our solution everyone who gets in contact with a Minor always knows it and becomes immediately responsible and punishable for what he/she does.
The caller's identity and his/her telephone number is always shown on the display and recorded in the call report/list.
You can't receive deceptive SMS such as: « You won €100. Send an SMS  back to this number and you'll get your recharge for free». In the case the child answers he/she would  pay a hidden extra cost.
No more pornographic MMS, nor enticement attempts.
Post that it's a "reato evento" (EVENT CRIME?), it's the Court of the Country where the Minor leaves that becomes competent to judge the fact.

Childkey Differentiated SIM as univoque identifier of the User/Owner Customer accomplishes the (Italian) law about privacy (Dlgs 196/2003) and other local laws (anti-terrorism and anti-money washing)