It appears Mediacom the (7th largest cable company in the US) is currently having DNS* issues again!
For information on how to change your dns to Googles’ DNS servers temporarily.
This will resolve any issues you have with Mediacom DNS
#Update 6:38PM some markets seem to be coming back online#
*Domain Name System (DNS) is a database system that translates a computer’s fully qualified domain name into an IP address.