An other paper from earthweb (definitly a good networking site!).
I found it very interesting as a good introduction to Public Key Infrastructure (PKI).
It may interest some AO around...

full article here
Understanding PKI

You don't need to be an expert in encryption to deploy PKI in your operation, but there are a few key concepts and components to understand. PKI is a powerful technology that employs cryptography to provide two important capabilities, privacy and authentication. The cryptographic procedures, or algorithms, use two keys to encrypt information. This is called asymmetric cryptography. Compared with conventional (symmetric) cryptography, which uses only one key, it is easier to distribute keys, making PKI much simpler and more practical to deploy.
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