Mobile Phones: Mobile Phone Unlocking
Introduction
The practice of 'locking' a mobile phone to a specific operator or service provider is a very common one and in many (but not all) countries this is done for both Contract Mobile Phone and Pay as you Go (prepay) Mobile Phones. There are two main reasons for a service provider to lock your phone to their network. For contract mobile phones the handset is provided either free or at a considerable discount so that it's in the network provider's interest to force you to use their network so that they can recoup their costs during the period of their contract with you. Though in prepay mobile phones you pay for the handset it's still in the interest of network providers to lock the phone to their particular service or network as this is how they make their money.
This locking of a phone to a particular network and provider is a capability built into all GSM phones by the phones' manufacturers themselves. This works by locking the phone to only accept SIM cards from any combination of the following: A specific country or group of countries; A specific network provider [also known as a service provider] (Orange, Vodafone, Cingular etc); A specific network; or specific SIM card types. In Europe, Asia and North America at least virtually all mobile phones are shipped with country and network provider locks. In addition, most modern phones have firmware installed on them which is specific to the network provider ie if you have a Vodafone mobile phone then it displays the Vodafone splash screen on startup and supports specific Vodafone features. It should also be noted that the firmware is separate from the locking mechanism. Thus if you unlock a Vodafone mobile phone to work with any network, it will still display the Vodafone-specific logos and features. It is possible to unbrand a mobile phone by uploading different firmware to the mobile phone handset. However this is procedure that shold only be attempted by experienced users.
To avoid confusion it should be noted here that Motorola, uniquely amongst mobile phone manufacturers, call the SIM lock a 'subsidy lock' (because handsets are subsidized at point of sale by the network provider) and to unlock the phone you will need to obtain a 'subsidy password'.
The main reason to unlock a phone is to be able to use it with a different SIM card. For example, when travelling abroad it's usually cheaper to temporarily use a foreign network. Contrary to some beliefs, an unlocked phone can't access extra cell phone towers or give free phone service. All it can do is accept other SIMs.
Unlocking your Mobile Phone
SIM lock types explained
The Country Lock — This type of lock restricts the use of the mobile phone only to SIM cards that originate in a specific country or group of countries. So, for example a phone locked to the US cannot be used in the UK. But a phone locked to Western European countries could use any SIM card from any country in the EU.
The Network Lock — This kind of lock restricts the mobile phone to SIM cards that belong to a specific network. But, as some service providers use the same physical network this type of lock could enable you to use SIMs from multiple service providers.
The Service Provider Lock — This is by far the commonest kind of mobile phone lock and it restricts the use of the phone to only those SIM cards provided by the service provider who sold you the phone. With this kind of lock it is sometimes possible to buy a cheap pay-as-you-go handset from the same service provider and use your contract SIM card in this. However, service providers are clamping down on this usage by effectively placing their contract and pay-as-you-go mobile phones on different virtual networks so that a contract SIM cannot be used in a PAYG mobile phone.
Full SIM Lock — This is by far the most restrictive kind of lock and only allows the mobile phone to be used with a single, specific, SIM card. If this SIM card is damaged or lost then the mobile phone is useless unless it can be reset or reprogrammed.
SIM Unlocking by Network Providers
The laws on SIM locking vary by territory. However, in most countries netwwork providers have either a mandatory or a voluntary duty to unlock the customer's mobile phone. In the US there is no mandatory requirement for service providers to unlock phones. Some providers never unlock phones, whilst others will only unlock phones if you have had an account in good standing with them for at least 90 days. Belgium does not allow any network to sell locked handsets and the same is true for Hong Kong (with the exception of PDA phones such as the BlackBerry). In the Netherlands service providers must provide unlocking codes, but are allowed to charge a fee within the first 12 months after the purchase of the phone. Thereafter the unlocking code is free. In the UK service providers are required to unlock a mobile phone if requested to do so. But they are allowed to charge a fee (usually around £30) for this service. This has led to a mini-industry in the UK of both internet and high-street unlock stores that sell cut-price unlocking (usually at £10–£15).
The Unlocking Process
The exact means by which a phone can be unlocked depends both on the mobile phone's manufacturer and the service provider. In most cases, however, a mobile phone can be unlocked either by entering a special code into the handset but its keypad, by direct programming from a computer or (in some cases at least) by the transmission of a code over-the-air by the network provider. Because there are several kinds of SIM locks, there are also several kinds of unlock code types. But only one kind of unlock code removes all SIM locks from a phone and this is the master code (also known as the network code key). This unlock code is either stored in the manufacturer's central database (as for Motorola phones) or is calculated by the manufacturer based on a rather obscure algorithm that uses the phone's IMEI (International Mobile Equipment Identity) and the MCC (Mobile Country Code List).
If you perform an internet search for 'Mobile Phone Unlocking' then you will encounter many free and paid sites offering unlocking for Nokia phones. Indeed, Nokia unlocking sites far outnumber all other unlocking sites on the internet. This is because the algorithms used to generate unlock codes for earlier Nokia phones ave been reverse engineered, stolen or leaked, resulting in many people offering nokia unlock codes for free or for a fee. It should be noted though that the newer Nokia models have far more robust algorithms built into them and thus are not unlockable by the free applications provided on the web.
Many of the other major manufacturers took a more cautious approach and now embed a random number within their mobile phones' firmware that is specific to the network on whose behalf the original SIM lock was applied. These phones can still be unlocked but they have to be connected to specialist test equipment that physically over-writes that portion of the phone's firmware where the lock status is kept. In addition, most manufacturers also limit the number of times that users can attempt to enter the unlock code (usually five). After five unsuccesful attempts the mobile phone becomes 'hard-locked' and after this specialized unlocking equipment is required to unlock the handset.
One of the most popular ways of unlocking mobile phones is to use a computer. The phone is connected to the PC via an USB or RS-232 port and software specifically written for the model of phone being unlocked is used to communicate with the handset and unlock it. Many such software and connect cable combinations are sold on auction sites such as eBay. These often work with older telephone models, but be cautious if buying such software to unlock one of the more recent phone models as the software usually lags between at least year and eighteen months behind the release of new mobile phone models. As well as PC-based software it is also possible to obtain unlocking clips or unlocking boxes that physically re-program the software that controls the phone, removing the SIM lock. However such hardware is expensive and is only economically viable if you are going to unlock a large number of phones.
As a final caveat it should be noted that unlocking a phone without the permission or unlocking code from the provider is usually in breach of the agreement with the provider, though most countries do not make specific laws prohibiting the removal of SIM locks. (In many markets, it is also unlikely that a customer who has purchased a pay as you go phone over the counter in a store is legally bound by any such contract anyway). In the UK, under the provision of the Mobile Telephones (Re-programming) Act 2002, it is stated that changing the IMEI of a phone is illegal. But the IMEI is never modified during the unlocking process. In the US, a change to the copyright laws on November 26th 2006 now makes cellular phone unlocking legal, though the legislation expires in three years' time.
If you are looking for mobile phone unlocking sites my Mobile Phone Links page lists a number of unlocking providers.