CFExchangeConnection

We are having problems establishing an exchange connection. We have a couple of things we don't quite understand since I am new at this.

1. We have 2 exchange servers front end and back end. Which one do we connect to?

2. Our environment does not require a password after the user is authenticated on our site. Do really need to pass a userid and password or is the userid sufficient? I ask because the documentation says the password is optional.

3. What would the correct code look like for both an HTTP and HTTPS connection?

4. Which folder do these certificates go into?

(Our Current Code)

<cfexchangeConnection
    action="open"
    connection="MyConnection"
    server="servername"
    username="#CGI.AUTH_USER#"
  protocol="https">

Any insight or articles that I can read on this subject would help a lot. Thank You