Re: message digest of large files

From: Volker Hetzer (volker.hetzer_at_ieee.org)
Date: 08/17/05


Date: Wed, 17 Aug 2005 17:18:12 +0200

Regis wrote:
> On Wed, 17 Aug 2005 17:32:44 +1000, James Whitwell
> <jams@momento.com.au> wrote:
>
>
>>Hi,
>>
>>We're trying to use message digests as a way to uniquely identify large
>>binary files (around 50-60MB). Is there a limit to the size of the file
>>that we feed through, say SHA1? I was thinking we could start a new
>>hash every 10MB or so. Is there any information on this topic that
>>someone could point me to?

Yes, there is a limit. SHA1 is certified up to 2^64 bit, i.e. 2048 Exabytes
(1024 as factor). Ditto for SHA-256.
SHA-384 and SHA-512 are good for 2^128 bit.

Lots of Greetings!
Volker