What is Jailbreak?

[Austin S.]

I hear it a lot... I am gettign an iTouch 2nd Generation for Christmas, and jsut want to know what "Jailbreak" is and how to do it?

 

[Ice-Cube]

In simple terms, it means "opening' up the Phone's Operating System so that 3rd-party software could be installed on it. You could also tweak many system settings which a normal iPhone wouldn't have.

 

[Austin S.]

Ok, I see. Thanks for the reply!

 

[SnowLeopard2008]

Careful if you wish to jailbreak, if you have an iPhone 3G, there's a chance you might brick it. permanently. It also might render it unstable w/ choppy animations and slow boot up times.

 

[nikhilr51]

Cant jailbreak

Hi,
I bought a 2ng gen touch and i thought you should know that its not possible to jailbreak it yet. Jailbreaking lets you do these things and more:
-Access files on your touch
-Download pirated app store apps (just saying that you can)
-Install cydia (like app store)
-other stuff....

I have set my homepage to http://blog.iphone-dev.org/ (yes its a bit sad)
as the dev team are the people who are working on the jailbreak.

Nikhil R

 

[4np]

A 'jail' generally means you are in an environment that is seperated from the operating system (also known as sandbox). The reason for the jail is security, the application that runs in the jail (and the user using it) can only access parts of the operating system the system designer allows it access to. Hence, in order to get to the operating itself, one needs to break the jail. Generally a jail shares (system) software and/or libraries with the operating system. Breaking the jail can be done by exploiting bugs in these shared applications/libraries that have access to the operating system. However, when the particular bug used by the exploit is fixed by apple (or the developer of that particular piece of code) that method for breaking jail will not work anymore. So one needs to find another bug to exploit. And you need access to the operating system to be able to install software on it, or to get to the baseband. Probably the people behind the jailbreak methods have already found a number of exploits they can use if the current one stops working. But, what if all bugs will be fixed? Then there will be no way to jailbreak the platform anymore. So it would be good if they found another way to break into the operating system.

A bit technical example of Apache (webserver) running in a chroot jail on a Linux server. Left is the operating system (Linux) and right is the jail (with a sub-set of system software) running the application (Apache). In this example Apache can only access the files in it's own jail, not the operating system itself. Apache is not even aware of the operating system or that it is in a jail, from the perspective of apache it is running on an operating system itself. But in fact it's an isolated trimmed down little area with only the necessary files available for it's own task. As for the iPhone/iPod Touch, I'm not sure if the window server (the springboard) + application run in one jail, or if every application is running in it's own seperate jail.