Net :: ERR_TIMED_OUT when sent to ACS url

I am integrating 3D Secure for a payment gateway and keep getting a timeout error when I try to send a message to https://dropit.3dsecure.net:9443/PIT/ACS .

Failed to load resource: net::ERR_TIMED_OUT

Has anyone else encountered this? Anything I can do about this, or is it just my internet connection?