Ian Ball is an expert on the mobile communications industry
SIM lock is a feature that is particularly designed by mobile phone manufacturers and it is an in-built system embedded into GSM phones. The main motto of the SIM lock feature is to accessibility of network providers to limit the use of their subscribers’ phones up to specific region (mainly countries) and to certain network providers.
At present, the SIM lock is dependent on three modes of operation:
· The type of SIM: It implies that only a certain type of SIM can be used in a particular mobile
· Network service provider: It implies that the connectivity will be restricted depending upon the network service provider, for example, T-Mobile, AT&T
· Country specific: It implies that the phone will be workable in a particular country, but not in the other
Types of SIM locking
Essentially there are three types of SIM locking features available in the market. The hardest and most difficult type of lock is SIM card lock; this implies that a phone is workable with only one SIM. This is difficult in terms of changing the mobile itself once the SIM gets damaged.
The most commonly used SIM lock option is service provider lock or SP lock. It depends on the physical network that many of the service providers may access. When SP lock option is enabled, it affirms that the user can only use the SIM cards for the particular service provider. This is particularly useful for pay as you go mobile phones.
The SIM card made as country specific is workable within a specific country or group of countries in particular.
Laws on SIM locking
The laws governing SIM locking system is entirely dependable on different companies. In case of particular providers like AT&T Wireless, it never allows unlocking to its customers, whereas the new AT&T allows unlocking to its customer after 3months successful standing on their part.
There are various rules in different countries that are truly dissimilar than others. For example, in Belgium, the act governing the communication does not support any locking feature in mobile phones. Therefore all of the mobile phones sold in Belgium need to be unlocked.
The laws are quite different in Netherlands and Spain where the service providers need to deliver the unlocking code along with the mobile phone at the time of selling. This may be chargeable for an initial duration of 12 months in some cases.
On the other hand, in Hong Kong and Finland carriers in particular are not eligible to sell locked mobile phones to their customers; however, exceptions are there for particular sets.
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