Many i Phone owners have probably heard the the term “baseband” or perhaps read or heard about baseband upgrades.The purpose of these i Phone baseband upgrades is to improve the functionality of the cellular modem that is on the device, and the low level firmware (software) that is contained within the baseband.You will be using fixrecovery43 for this process, and any process that has to do with i OS 4.3.x. Once the process described above has been followed exactly, you are done with your restore, and you are now running i OS 4.3.3.on your i Phone 4, with your old baseband still active on the device.Tools like Tiny Umbrella have allowed you to save the SHSH blobs, so you can use it to create (stitch) a pre-signed IPSW file, which could then be used to restore your device with an i OS version that Apple was no longer signing.
If your i Phone has baseband , you will still be able to successfully unlock the i Phone 4 today.
The new i OS update from Apple will also update your modem firmware, or baseband, which will pretty much eliminate your chances of unlocking your i Phone right now.
Unless an update is made for Ultrasn0w, you are pretty much out of luck…
All i Phones have a baseband, and i Phone baseband is essentially the cellular modem firmware that is on your i Phone.
Specifically, baseband includes the low level software that is running on the i Phones cellular modem hardware, the combination of which allows the i Phone to connect to a cellular network to send and receive data, phone calls, and transmissions.
The lower you keep your baseband, the better your chances of an unlock are! After you have prepared yourself properly with the tools needed from above, you are ready to start the process of updating.