Question: OAS + SSL + certificate

Question

How I can take client X.509 certificate information on OAS side by using servlet or different way?

Answer 1

There are cases where you don't have a trustworthy and reliable way to pre-load certificates.
Where you want or need to have a chain of authority back to a pre-loaded root CA.
Where you're unwilling to learn how to create and load (securely) your own root CA.
Or unable to get your own root CA loaded onto the client boxes in a secure fashion.
Yes, certificates can be a component of mail's client-to-server communications; useful and used for communications between your mail client(s) and your mail server.
No, SMTP mail servers don't use certificates for server-to-server communications, and don't encrypt these server-to-server port 25 communications. These communications are "authenticated" using the reverse DNS and the MX record of the sending server, and potentially gray-listing and anti-spam services such as Spamhaus Zen.
Here's an old [SSL Cert How-to|http://www.eclectica.ca/howto/ssl-cert-howto.php] and see [cacert.org|http://www.cacert.org> and see [how to install trusted root certificates|http://www.askdavetaylor.com/howto_install_trusted_root_certificatemac.html] and some interesting reading at [hacker news|http://news.ycombinator.com/item?id=1244444], among other sites.