What is a Certificate?
Certificates are issued to web servers to enable secure connections between the web browser and the web server. You have encountered certificates if you use on-line banking web sites or other web sites with valuable information.

Why is my browser warning me about the site's security?
Our site's certificates are issued by the Department of Defense as required by policy. Certificates are verified by an intermediate Certificate Authority and a Root Certificate Authority. Commercial browsers such as Internet Explorer, Chrome, Safari, Firefox and others do not recognize these Certificate Authorities as valid, thus they don't "trust" them. However, the Certificate Authorities (abbreviated as CA) are valid and the certificates issued are valid. When you connect the connections are very secure using the highest possible encryption available.

How do I verify the certificate was issued by DoD?
Look at the URL bar for your browser. You will see a padlock icon to the left of the URL. Click that padlock, our site's security information will be displayed. Depending on the browser various viewing options are available. Ensure the certificate authority states "DoD Certificate Authority" followed by a number. If so you have connected to our site.

More Information
DISCLAIMER: The Department of Defense nor the Defense Imagery Management Operations Center (DIMOC) endorse these web sites, they are provided for your information only.

Military CAC.com (Blocked on most DoD systems) - Lots of information, focused on making the DoD Common Access card work for home users, but contains valuable information about DoD PKI.

Bug 525250 - DOD Root CA 2 is untrusted - Discusses why DoD certificates are not recognized by browsers, in particular Firefox.