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 From: Sergey Karimov
  Where is Sergey Karimov?
 Reston
 Virginia - United States
 Sergey Karimov
 To: Mz
  Where is Mz?
 Metro Manila
 Philippines
 Mz
 Tags
Subject: RE: An adhoc Article... mzhash
Thread ID: 50901 Message ID: 51378 # Views: 3 # Ratings: 0
Version: Unknown Category: Other
Date: Saturday, September 11, 2004 3:42:35 PM         
   


> Therefore, the data to be sent is 12345678 where 8 is the checksum. The problem in this kind of Checksum,
> is that when we interchange the numbers. say 7654321, then we compute:
>
> 7 + 6 + 5 + 4 + 3 + 2 + 1 = 28 where the modulo is also equal to 8
>
> So whats the problem with this? The problem is that when we have a string say 'hello' the simple checksum is the
> same for 'olleh' or 'helol'.
>
> Because of that, there are new technologies and mathematical computation that arises and there comes the HASH.
> The same results will also arise for a longer string of lets say 100MB of File. A 1 or 4 byte of CRC is not enough
> for the accuracy of it... so far MD5 is the most reliable and secured HASH algorithm.
>
> -Mz

I see, a control sum is just a one algorithm (usually additive) to calculate a hash code. But by the way in the examples you posted we have exactly the same problem as with 'olleh' and 'helol':

www.foxite.com 20040801 = 0178387634
www.foxite.com 20040810 = 0178387634

www.foxite.com 20040802 = 0780136767
www.foxite.com 20040820 = 0780136767

www.foxite.com 20040812 = 0502775015
www.foxite.com 20040821 = 0502775015

www.foxite.com 20040803 = 0694851974
www.foxite.com 20040830 = 0694851974

Regards,
Sergey

ENTIRE THREAD

The strength of Logarithm... Posted by Mz @ 9/7/2004 4:06:53 AM
RE: The strength of Logarithm... Posted by Wild Fire @ 9/7/2004 4:23:00 AM
RE: The strength of Logarithm... Posted by Alexander Federizo @ 9/7/2004 4:56:54 AM
RE: The strength of Logarithm... Posted by Mz @ 9/7/2004 5:07:57 AM
RE: The strength of Logarithm... Posted by Alexander Federizo @ 9/7/2004 6:40:06 AM
RE: The strength of Logarithm... Posted by Mz @ 9/7/2004 7:00:06 AM
RE: The strength of Logarithm... Posted by Alexander Federizo @ 9/7/2004 7:23:24 AM
RE: The strength of Logarithm... Posted by Mz @ 9/10/2004 12:47:34 PM
RE: The strength of Logarithms... Posted by Alexander Federizo @ 9/10/2004 6:07:12 PM
RE: The strength of Logarithm... Posted by Boudewijn Lutgerink @ 9/10/2004 8:43:15 AM
An adhoc Article... mzhash Posted by Mz @ 9/10/2004 9:35:34 AM
RE: An adhoc Article... mzhash Posted by Alexander Federizo @ 9/10/2004 5:53:58 PM
RE: An adhoc Article... mzhash Posted by Mz @ 9/11/2004 4:30:58 AM
RE: An adhoc Article... mzhash Posted by Sergey Karimov @ 9/11/2004 5:10:55 AM
RE: An adhoc Article... mzhash Posted by Mz @ 9/11/2004 6:45:48 AM
RE: An adhoc Article... mzhash Posted by Mz @ 9/11/2004 7:00:53 AM
RE: An adhoc Article... mzhash Posted by Sergey Karimov @ 9/11/2004 3:20:46 PM
RE: An adhoc Article... mzhash Posted by Sergey Karimov @ 9/11/2004 3:42:35 PM
RE: An adhoc Article... mzhash Posted by Mz @ 9/12/2004 10:19:23 AM
RE: An adhoc Article... mzhash Posted by Sergey Karimov @ 9/12/2004 4:13:36 PM
RE: An adhoc Article... mzhash Posted by Mz @ 9/13/2004 3:19:33 AM
An approach for Intelectual Property Protection... Posted by Mz @ 9/11/2004 7:12:08 AM
RE: An approach for Intelectual Property Protec... Posted by Dale Dedoroy @ 9/13/2004 4:14:20 AM
RE: An approach for Intelectual Property Protec... Posted by Mz @ 9/13/2004 5:27:30 AM