How does phone unlocking work?

cursai

I'm curious. How do phone shops unlock phones. Surely whatever wizardry is done can be replicated by a layman. Its like the code of magic.
Ive never actually gotten a concise answer.

How do they do it?

Atlantic Dawn

Sometimes it's simply a code generator they use that unlocks the phone based on the EMEI number they enter. Have seen plenty on Ebay offering it via email after you pay them, just supply EMEI number and phone make and model.

ED E

The correct method is a NAC, this tells the baseband not to care about MNCs anymore.

The cheapo method on some phones is to flash custom firmware to skip this MNC check. Doing so can have side effects and can be undone by system updates etc. Its not uncommon for "Chinese phone shops" to do this.

cursai

Atlantic Dawn wrote: »

Sometimes it's simply a code generator they use that unlocks the phone based on the EMEI number they enter. Have seen plenty on Ebay offering it via email after you pay them, just supply EMEI number and phone make and model.

And how do they get access to this code generator. Its sounding like the little machine the mechanic has to turn off your alarm lights.

McMurphy

cursai wrote: »

And how do they get access to this code generator. Its sounding like the little machine the mechanic has to turn off your alarm lights.

I know back in the early 00's you used to be able to download Nokia unlock code generators for free from the web.

You used to have to enter details such as IMEI no, phone model, etc and it produces a code that you entered when prompted.

They weren't 100% reliable (I'd say 75%, if that)

I'm sure the unlock lads nowadays use some similar software.

dubrov

I know the Ebay unlock codes take a couple of days to generate for the s8/s9.

I'd guess the unlock code is based on some hashing algorithm. The codes are probably sent to a third party who have the required hardware to generate the unlock code by brute force..