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Re: p:hash : add CRC

From: Norman Walsh <ndw@nwalsh.com>
Date: Wed, 07 May 2008 07:40:50 -0400
To: public-xml-processing-model-wg@w3.org
Message-ID: <m2od7is5od.fsf@nwalsh.com>
/ Innovimax SARL <innovimax@gmail.com> was heard to say:
| Even if sha and md5 are very strong, weak use are still in place in V42,
| Ethernet, FDDI, ZIP and PNG
|
| They all use a CRC
|
| I think we should allow a new value for algorithm 'crc' with three
| parameters provided on 'parameters' port :
|
| * size in bits (integer)
| * polynom as a String (or hexBinary)
| * polynom-form as a string amongst ("Normal", "Reverse" or
| 'NormalOfReciprocal")
|
| Option 1 : we could say there is no default so you need to provide the
| parameters
| Option 2 : we could say that if no parameters are provided, then it will be
| defaulted to size=32, polynom=0xEDB88320 and polynom-form=Reverse (which is
| CRC-32-IEEE 802.3 used in V42, MPEG 2 and PNG)

I'm ok with this. I prefer option 2.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | The world is a vast temple dedicated to
http://nwalsh.com/            | Discord.-- Voltaire

Received on Wednesday, 7 May 2008 11:41:22 GMT

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