Data Loss Prevention

Can any one describe me these 3 terms Reflect Mode Forward Mode and X-header.when i was go through Symantec DLP network Prevent for e-mail.i saw these terms.So any one eloborate these terms

Reflect mode is where the mail flow is as follows

MTA1 -> Email Prevent -> MTA1

Forward Mode is where the mail flow is as follows

MTA1 -> Email Prevent -> MTA2

An X-Header is the method by which we add information to the email envelope that is then acted upon by the downstream MTA.  In each case the header starts with the letter X. For example integrating with PGP's mail gateway we can add an X-header named X-Encrypt with a value of true which then tells the downstream MTA to forward the email to the encryption gateway as opposed to committing to final delivery.

John it means if we are using 2 MTA we will use always Forward mode.

John has very rightly explained. easy way.