:: NEW USERS READ THIS FIRST - Stuff you probably won't find in the WIKI ::

[Stormy]

Drakkhen

Thank you very much again.

One last question, is there a big advantage of keeping the 4.6 BL, I mean from useability or feature stand points cause I dont really understand the difference that much. If not then, I will go ahead and use Ziphone to unlock my 16gb

Thanks

[Drakkhen]

There is a difference in functionality, but not at the user level - only at the baseband level. Right now, if there is an advantage, it would be BL3.9, as it can run the newest baseband unlocked.

[ramb0]

There's quite a lot of discussion around the net regarding BL 3.9 vs 4.6.

Another reason why some people want to stay on BL4.6 is due to the possibilities of CUSTOM Bootloaders. As mentioned, we can modify the Bootloader if it's version 4.6 (for example, downgrade to 3.9). This means if a custom BL is developed, only people that are currently on 4.6 would be able to load the custom BL. How ever, it may also be possible for someone to develop a hack that allows upgrading/modifying of the 3.9BL as well, although this is unknown.

Custom Bootloader? Well, a Custom Bootloader could potentially mean that all future versions of the iPhone will be easily hacked, as the Bootloader is the main key of the iPhone.

Keep in mind though, the time will come where Apple released a new iPhone, which will no doubt have different hardware properties, and include everything Apple has learnt so far from the hacking scene.

[garykaifong]

There's quite a lot of discussion around the net regarding BL 3.9 vs 4.6.

Another reason why some people want to stay on BL4.6 is due to the possibilities of CUSTOM Bootloaders. As mentioned, we can modify the Bootloader if it's version 4.6 (for example, downgrade to 3.9). This means if a custom BL is developed, only people that are currently on 4.6 would be able to load the custom BL. How ever, it may also be possible for someone to develop a hack that allows upgrading/modifying of the 3.9BL as well, although this is unknown.

Custom Bootloader? Well, a Custom Bootloader could potentially mean that all future versions of the iPhone will be easily hacked, as the Bootloader is the main key of the iPhone.

Keep in mind though, the time will come where Apple released a new iPhone, which will no doubt have different hardware properties, and include everything Apple has learnt so far from the hacking scene.

Someone (sorry I'm a bit lazy to go back to check who while I'm typing the reply) mentioned that one possible answer why there is not yet any upgrade from 3.9BL to 4.6BL is because of zero demand. Assuming that this is THE reason, and if there really comes a Custom BL which requires 4.6BL, wouldn't it then attract users' attention/interest in going back to 4.6BL, and thus generate enough demand? Just for argument sake. ;-)

Actually, I found this thread really helpful. I still haven't got myself an iPhone, partially because of this BL downgrading issue. Now, I think at least I sort of understand what a BL does, and what a downgrade could possibly mean. I think I'm going to order one, but yet I want to wait until the upcoming Apple Event which I was told will be on 6-Mar-08. Is that correct?

Ciao,
Gaz

[JosueCebs]

This was in response to a post that was deleted by the OP on this thread. The post asked:

• I heard that using new ZiPhone method to unlock the iPhone will downgrade your BL to 3.9 but also you will not be able to upgrade the BL in the future. Is this true?

The answer is yes AND no.

Right now, there is no easy guide or method that you'll be able to find that will help youu upgrade to back to 4.6. This is not a fault of the ZiPhone method of downgrading. The simple fact is, no matter if you'be downgraded to 3.9 from 4.6, or if you started at 3.9 O.O.B, there's is no BL upgrade.

I think part of the reason one hasn't really been developed is, that there is zero demand. 3.9 is the bootloader of choice as it is still less restrictive. People who start off with a 3.9BL have obviously no reason to upgrade, and people who have 4.6BL phones either want to stay put or downgrade. So, unless there is actualy incentive to go to 4.6 I don't see one actually being developed.

I'm sure that upgrading from 3.9 to 4.6 is possible; just as it was possible to downgrade, but why? If we answer 'why', then we'll get an end user solution to do so.


L.

I have one possible answer to why..

My reason at least would be for return or repair to apple. A downgraded Bootloader would be an automatic flag for apple that you have modified your iphone. Having the ability to upgrade/restore your original Bootloader version (be it through a GUI or command line) would be a true means of re-virginizing the iPhone in the "rare" cases where it would have to be turned in for repair or replacement.

I say "rare" because after giving this some thought, and as I'm sure you are aware, anyone who is unlocking their iPhone for use outside of AT&T (or even within AT&T but outside of an iPhone plan) will not be hapilly received for repair. According to something I read devices not activated for use in AT&T (with an iPhone plan) will only be covered for the first 30 days of the device warranty. In order to have the regular hardware warranty period of 1 year you must have a currently active AT&T iPhone account when turning in the iPhone for repair or replacement.

Even so, a Bootloader upgrade/restore utility would be nice for those who will be returning or repairing their iPhones within that 30 day period...

[XFF]

Your computer and its HAL actually detects a DFU enabled phone as an entirely different device (and uses a different driver) compared to a phone that is in normal restore mode. This alone should tell you that there is something intrinsicly different about the two modes. When doing a restore, the method in which your computer uses to communicate to the phone differs vastly between the two.

Can you elaborate on that a little bit? I'd like to better understand what the difference is between DFU Mode and Restore Mode. I suspect that in DFU mode, all the user information on the device is disregarded and the DFU driver only interfaces with the bootloader. Is that correct? But does the DFU Mode restore end up the same as a Restore Mode restore and only the way it gets there is different, or are there differences in how the phone is provisioned with either method? Why do the two modes exist in the first place? Was DFU mode only designed as a last resort when all else fails? If so, what's the tradeoff?

[Drakkhen]

Can you elaborate on that a little bit? I'd like to better understand what the difference is between DFU Mode and Restore Mode. I suspect that in DFU mode, all the user information on the device is disregarded and the DFU driver only interfaces with the bootloader. Is that correct? But does the DFU Mode restore end up the same as a Restore Mode restore and only the way it gets there is different, or are there differences in how the phone is provisioned with either method? Why do the two modes exist in the first place? Was DFU mode only designed as a last resort when all else fails? If so, what's the tradeoff?

Well, the computer system actually sees the unit as a completely different device when it is connected through DFU mode when compared to restore mode.

My guess is that the difference is in how data is actually written to the device. DFU mode uses a more low-level way of writing; possibly even using your computer's file structure logic to place data on the phone, while the regular restore mode may use part of the iPhone's file structure logic as a filter.

A good analogy would probably be writing to your file system on your PC using Windows NTFS (in windows) vs. creating a bootsector that lets you load multiple OS'es...

L.

[Jaguilera85]

Very good information. Thanks!

[gnodmena]

hi guys i really want an iphone since i just broke my pearl a couple days ago. so i guess my question is what is the worst thing that could happen to the phone once i unlock it and jailbrake it and all that good stuff ??? oh yeah i will be putting a rogers sim in it. is there anything i should be aware of??
thanks

[onli1]

very imformative, thanks alot for you help in this forum

[swankmetal]

is all the info in this thread still accurate? just wondering because i just got one of the refurbs and it came with 1.1.2, week 40. from what i've read, this is a good thing. not quite sure what route i should use for unlocking, etc. though.

[Sethisis]

I would also like to hijack this thread, and not clog up with a new post.

can I still jailbreak my phone and use it on ATT fully?

I currently have the iphone plan and just dont want to screw anything up by doing this. Didn't see anythingin the faq or wiki. Probably a stupid question

[Drakkhen]

is all the info in this thread still accurate? just wondering because i just got one of the refurbs and it came with 1.1.2, week 40. from what i've read, this is a good thing. not quite sure what route i should use for unlocking, etc. though.

The information here does not take into account refurbs, as apple may choose to upgrade the bootloader, or keep it the same.

L.

[help_questions]

perhaps someone could add to this the mistakes some people that end up making their iPhone unusable due to failed unlocking/jailbreaking.

[shakenbake]

Can you elaborate on that a little bit? I'd like to better understand what the difference is between DFU Mode and Restore Mode. I suspect that in DFU mode, all the user information on the device is disregarded and the DFU driver only interfaces with the bootloader. Is that correct? But does the DFU Mode restore end up the same as a Restore Mode restore and only the way it gets there is different, or are there differences in how the phone is provisioned with either method? Why do the two modes exist in the first place? Was DFU mode only designed as a last resort when all else fails? If so, what's the tradeoff?

Good info from the hackintosh site:

http://www.hackint0sh.org/forum/showthread.php?t=27348