[BitTorrent] BT2 & hash trees

John Hoffman theshadow at shambala.net
Thu Jul 22 23:18:33 EDT 2004


*FLAME ON*
Damn it, Olaf, don't pontificate on shit if you aren't going to do the 
research!  I'm telling you, I ran tests, I looked at what other systems 
use.  I went looking for source code for Tiger tree handling, looking to 
convert it to Python, and that's how I found out what I know.  I ran 
tests on hash generation.  If you disbelieve me, then go look for your 
god damned self.  Don't imply I'm a liar while talking out of your ass.


>>>>I considered recommending using THEX as the algorithm for BT2, but THEX 
>>>>is based on the Tiger hash, and on a low-iteration version of the hash 
>>>>        
>>>>
>>>Where does it say that?
>>>
>>>      
>>>
>>Read the spec, look at the implementation.
>>    
>>
>
>This part?
>For instance, the SHA-1 algorithm is identified by ...
>The Tiger algorithm is also supported and is identified by ...
>
>  
>
>>>>I did some tests and calculating hashes on such a fine-grained level 
>>>>does impose a significant amount of additional overhead, and since BT 
>>>>  
>>>>
>>>>        
>>>>
>>>What kind of overhead?
>>>More (complex) code?
>>>More CPU?
>>>More RAM?
>>>More network?
>>>
>>>      
>>>
>  > Significantly more CPU.
>
>During what operation?
>There's almost no difference in complexity between computing the hash of 
>a 16 kbyte block directly or via 1 kbyte base blocks.
>



------------------------ Yahoo! Groups Sponsor --------------------~--> 
Make a clean sweep of pop-up ads. Yahoo! Companion Toolbar.
Now with Pop-Up Blocker. Get it for free!
http://us.click.yahoo.com/L5YrjA/eSIIAA/yQLSAA/dkFolB/TM
--------------------------------------------------------------------~-> 

 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/BitTorrent/

<*> To unsubscribe from this group, send an email to:
    BitTorrent-unsubscribe at yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
 



More information about the BitTorrent mailing list