to deal with the mail
2.The stickiest issue is building a directory of digital certificates. This directory holds the certificates needed to encrypt messages to a recipient. Internally,building the directory may not be a big deal because all certificates for a company can be published in a central Lightweight Directory Access Protocol server,but externally this causes many problems. You will need to establish an agreement with a recipient’s organization to ensure access to the right digital certificates. This process, however, creates more user training issues and adds complexity to e-mail communications.

