Identifying your Internet mail gateway

Your Internet mail gateway is the last server in your organization through which outbound email is currently routed.

You can identify the gateway by examining network diagrams. If these are not available, we recommend sending an email message to an external account such as Hotmail or Gmail and examining the message headers of the external mail. The message headers show the route the message has taken through your organization.

For example, the text below shows the routing of a message from Forcepoint to Gmail. Ordinarily, mail systems show the routing consecutively. This routing is shown in reverse order. In this header, you can see 2 gateways in bold: the gateway for Google and the gateway for Forcepoint. The server that passes the message to the Gmail system is mail.forcepoint.com.

(cluster- f.mailcontrol.com [85.119.2.190])
by mx.google.com with ESMTP id 
u9si14538601muf.12.2008.07.17.09.24.14; 
Thu, 17 Jul 2008 09:24:15 -0700 (PDT)
Received-SPF: pass (google.com: domain of 
someone@forcepoint.com designates 85.119.2.190 
as permitted sender) client-ip=85.119.2.190;
Authentication-Results: mx.google.com; spf=pass 
google.com: domain of someone@forcepoint.com designates 
85.119.2.190 as permitted sender) smtp.mail=someone@forcepoint.com 
Received: from mail.forcepoint.com by rly08f.srv.mailcontrol.com 
(MailControl) with ESMTP id m6HGNM8O024741
for <anyone@gmail.com>; Thu, 17 Jul 2008 17:24:01 +0100 
Subject: Test message
Date: Thu, 17 Jul 2008 17:23:45 +0100
From: "Doe, John" <someone@forcepoint.com> 
To: <anyone@gmail.com>