The Netlock function is implemented when the cell phone is configured and is comparable to SIMlock, but Netlock can be used to restrict services and exclude countries.
Netlock is therefore tied to the SIM card provider or network operator. Changing the SIM card does not mean that the user can make calls in a different mobile network. Since different network operators support multiple networks, the restrictions are often not severe. Netlock is tied to the contract period and can be unlocked afterwards free of charge or for a fee. When unlocking, the cell phone user receives an unlock code from the network operator.