Web Services - Non-repudiation

Hi,

I want to implement all the core requirements of security like
Authentication, Authorization, Privacy, Integrity and Non-repudiation.

From the search on the web, for acheiving Non-repudiation we can make use of
XML Digital Signatures.
But, i didnot find any information regarding the timestamping. XML Digital
Signatures can prove the source of origin but how can we take care of Time
Stamping so that we can prove that the sender as digitally signed before the
expiry or revoking of his certificate.

If i am wrong, please guiding me for acheiving non-repudiation in web
services.

Many Thanks and regards,
Srini
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Received on Wednesday, 24 April 2002 01:05:12 UTC