SHA-1 break - in perspective

[Kiefer, Sascha]

Funny it's the same calculation i had last night before i went to bed!
So long.
Sascha

16. Februar 2005 21:56, Atom Smasher wrote:
> To: recipient list not shown:
> Subject: SHA-1 break - in perspective
>
> this should help put the (alleged until proven otherwise) 
> SHA-1 break into 
> perspective. thanks to Sascha Kiefer for giving me the idea.
> 
> let's say that unbroken SHA-1 represents a 100 meter (328 ft) 
> wall. if a 
> break allows a collision to be found in merely 2^69 operations (on 
> average), that would mean the wall has crumbled to 4.9 cm 
> (1.9 in) tall. 
> that's broken!!
> 
> OTOH, let's say that unbroken MD5 represents a 100 meter (328 
> ft) wall. 
> comparing unbroken MD5 to broken SHA-1 means the wall would 
> actually grow 
> from 100 meters (328 ft) tall to 3.2 km (1.99 miles) tall. 
> SHA-1, even if 
> it's broken enough to find a collision in 2^69 operations (on 
> average), is 
> still stronger than MD5 was ever meant to be.
> 
> again, using unbroken MD5 as our reference of a 100 meter 
> (328 ft) wall, 
> unbroken SHA-1 would be a wall 6553.6 km (4072 miles) tall. SHA-1 was 
> intended to be incredibly stronger than MD5.