sendmail (Smart Host) authentication with server using certificates
 

We are trying to prepare a setup with following configuration:

We have a Central mail server which acts as a gateway to the internet for our domain.

We have some client machines which access internet via a box running sendmail setup as SMART HOST with authentication enabled to communicate with the server.

This is working fine now.

I have been asked to explore the option of authentication via certificates and keys in sendmail. I have been told that the user might want to provide certificates instead of Auth Info.

I know that sendmail.cf has an option of providing certificates. But... Is this possible/required? or is this another method of client-server communication in case of sendmail? Will login id and password not be required with Certificates?

Would appreciate if someone can provide answers to these questions and resolve these doubts.

PS: Found a good article on sendmail with certificates (for STARTTLS), but looks like its for the server and not for the client which in my case i need configured on the box.
http://www.openbsd.org/cgi-bin/man.c...86&format=html

Regards

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