I'm not asking will they, but does Apple have the capability to sign a lower baseband for individual iPhones that can connect to iTunes and downgrade? Meaning if I call them up and say that I want a lower iOS and baseband, can (not will) the tech adviser do this through iTunes? Or is it a system wide thing out of their capability?
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Can Apple manually sign previous basebands for individual iPhones?
- Thread starter chuckd83
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uhhm, could Jesus really walk on water?
The answer to your question is of course yes. They are most certainly technically able to let certain UDID's pass signature checks, through white listing, on lower firmware version. But they won't.
btw, you seem to have confused baseband w/ firmware
The answer to your question is of course yes. They are most certainly technically able to let certain UDID's pass signature checks, through white listing, on lower firmware version. But they won't.
btw, you seem to have confused baseband w/ firmware
Bb is hard coded. You have to replace the bb chip to get a lower bb. Factory unlock phones are the only ones that retain unlock on bb>1.59.
Supposedly, there's a place in China that'll replace the chip to lower your bb, but I can't vouch for its reliability. Also, you're without your phone for a while. It's around $80-90.
Supposedly, there's a place in China that'll replace the chip to lower your bb, but I can't vouch for its reliability. Also, you're without your phone for a while. It's around $80-90.
While I agree that apple is very unlikely to help you. You can downgrade the baseband on an Iphone 4 only since it has a signing procedure that technically allows downgrades on both firmware and baseband. There is no know way to downgrade the baseband on a 3gs.
Actually with the iPhone 4 you could downgrade the baseband if you were able to store the SHSH (or whatever it would be for the BB) for them. The dev-team and others haven't been able to figure out how to store the BB SHSH because it is different every time it is requested. Basically it doesn't stay the same like SHSHs do for the firmware. People have in the past (on this forum) downgraded their BB back to the official BB after they tried out one of the iOS betas. So it is possible but Apple has to still be signing the BB you want. Hopefully notcom, the dev-team and others find a way to store the BB SHSH so we can easily downgrade the BB and make the phone unlockable at will.
I don't think this is possible with the 3GS/3G/2G since the BB is handled differently than the way it is now handled on the iPhone 4. I think the way the iPhone handles the BB was actually meant to be a security feature so you had to upgrade your BB and couldn't stick with the old unlockable one/s but it kind of blew up in Apple's face since it allows us another way to preserve the BB when upgrading to a newer iOS.
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Yes they "technically" can, I don't think they can do it over the phone, they will need an special instance of their server (one just like the special instance that Tiny Umbrella creates). But yes If they wanted to, they can, those special instances already exits on test stations and refurbishes facilities.
Will they ever do it? well, you know the answer to that.