What do different IP addresses mean?

Generally speaking, you can determine the state of your connection from your IP address.
The most common examples follow.
173.x.x.x - This means that your computer has a connection directly to your modem, which
has been assigned by Mediacom's DHCP server. You should have a working connection like
this. If you are not able to connect to the internet, your modem may be in standby.
192.168.100.x - This IP range means that either your modem is currently in standby, or it
has not connected to our network. Check to make sure the coaxial cable is attached tightly.
192.168.x.x - This IP range can mean one of two different things. Either your computer is
connected to a router, or the modem you are connected to is in a standby state.
10.x.x.x - This means one of two different things. Either your modem is not receiving
proper registration information from our system (contact us), or you are using a router
which assigns to an unusual IP range. Routers that provide 10.x.x.x IP addresses are very
uncommon, but do exist.
169.254.x.x - The device is unable to communicate with a DHCP server. If you are
connected to a router, this commonly indicates a router malfunction. If you are connected
to our modem, it may indicate that we are having a system problem. In either case, it
could also indicate that your computer is unable to communicate out properly, an issue
which may exist within either hardware or software. - This indicates that your PC is either running an extremely old OS which does not
know how to assign itself a 169.254.x.x address, or that there is a malfunction within either
hardware or software. In this case, we strongly recommend contacting a local computer
technician for support.