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Electronic documents digitaly signed - best soltution ?

Posted: Mon Dec 17, 2007 4:18 pm
by AHF
We want to produce electronic documents PDF format but with digital signature.
We use the Crw 11 to produce the PDf file.

What are the available solutions to digitaly sign documents ?

Antonio

Posted: Tue Dec 18, 2007 12:59 am
by Antonio Linares
Antonio,

You may use FWH function nFileCRC( cFileName ) --> nCRC to calculate the checksum of a file

If the file is modified, the CRC will be different

Posted: Tue Dec 18, 2007 1:26 am
by James Bott
There is a good discussion of digital certification and digital signatures here:

http://www.adobe.com/products/pdfs/Adob ... uide-c.pdf

And there are more white papers on the topics here:

http://www.adobe.com/security/digsig.html

This is an issue that we are all going to need to deal with sooner or later.

Regards,
James

Posted: Tue Dec 18, 2007 7:06 pm
by AHF
Antonio,

That function it's not enough as we need a digital signature in order to issue electronic documents accordingly to the actual law to replace the paper work.

We are obliged to signed and time stamp all electronic documents.

James,

I agree with you, for us it already a need because many clients want already to work only with these kind of documents.
Together with the E.D. we must also produce xml documents acc to each client defined format in order to be integrated directy and automatic in their own ERP systems.

To work with xml documents xHarbour seems to have quite good functions however regarding digital certofacation nothing seems to be done yet.

Thanks both for your comments.

Antonio

Posted: Tue Dec 18, 2007 8:01 pm
by James Bott
>To work with xml documents xHarbour seems to have quite good functions however regarding digital certofacation nothing seems to be done yet.

I think you are going to have to do this with a PDF print driver that has an SDK. I know Adobe Acrobat can handle this but it is probably the most expensive solution.

For more PDF print driver options, go here:

www.planetpdf.com

Almost any solution you find is going to require that you purchase a license for each copy of software that you distribute.

James