shsh blobs?

[JasonG]

ok so im new to jailbreak, just trying to get this stuff straight. from what i understand, shsh blobs save your firmware so that say, i accidentally upgrade to 4.3 when it comes out, and lose my jailbreak, i can downgrade back down to 4.2.1 using the saved shsh blobs correct? i saved them via tinyumbrella. and how often should i save them? just every firmware, or occasionally?

sorry for the noob questions

 

[Laelipoo]

From what I understand, you are correct. I save mine every firmware. That's just me though.

 

[Ipheuria]

You have the right result but wrong idea. When Apple releases a new firmware it confirms that your iDevice is allowed to install it. Once they release a new firmware they stop allowing the older firmware from being installed. So if you upgrade and try to install the older version through iTunes it will failed because Apple will not sign it to allow it. So the SHSH blobs are not the firmware it's the confirmation for your device on that firmware. So when you need to downgrade you point to the blobs instead of Apple and it confirms that you're allowed using the stored keys.

You should do it for each firmware because you don't want to go two versions back.

 

[JasonG]

Ok thanks. At least I had the right idea down haha.

 

[Ipheuria]

LOL yeah I just wanted to give you the info so if anyone else ever asks you know what to tell them. It's always better when everyone becomes more knowledgable.