and then what?

	-----Original Message----- 
	From: Russ Cox [mailto:rsc@plan9.bell-labs.com] 
	Sent: Sat 5/31/2003 4:54 PM 
	To: 9fans@cse.psu.edu 
	Cc: 
	Subject: Re: [9fans] compare-by-hash
	
	

	The paper seems correct on most things, but is unfair to Venti.
	
	Venti is closer to hashing than compare-by-hash.
	Venti does look for SHA1 hash collisions -- once a block with a
	particular SHA1 hash has been written, you can't write any
	others.  Therefore you can't possibly end up thinking there are
	two different blocks stored on the same server and represented
	by the same SHA1 hash -- the store of the second will fail!
	
	Russ