From the Navy Knowledge Online (NKO) or nko.navy.mil, you will obtain links to other websites under the Department of the Navy services.
Department of the Navy's websites are all secured and you may wonder why in some browsers like Google Chrome will prompt you an alert before accessing the nko.navy.mil website.
In Firefox you will have message like this:
Secure Connection Failed
wwwa.nko.navy.mil uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is unknown.
(Error code: sec_error_unknown_issuer)
While in Chrome:
The site's security certificate is not trusted!
You attempted to reach www.nko.navy.mil, but the server presented a certificate issued by an entity that is not trusted by your computer's operating system. This may mean that the server has generated its own security credentials, which Google Chrome cannot rely on for identity information, or an attacker may be trying to intercept your communications. You should not proceed, especiallyif you have never seen this warning before for this site.
Since, the said website is using a secured protocol the message coming from your browsers are just fine and you don't have to worry anything about it.
