Many modern modems have an internal IP address that can be used for diagnostic purposes, information on the modem status, error logs, MAC addresses, and even configuraion options in some cases.
Here is a short list of models and IPs you can use to connect to those modems:
Ericsson Piperider:
192.168.100.1Motorola Surfboard SB1500:
192.168.100.1Note:
For a list of routers management interface IPs please see our Routers FAQ instead.We also have an extensive database of over 3000 routers/modems and their corresponding IPs available
-here-If you think you can contribute to the database, please contact us with your modem brand/model and the IP address and port number, if applicable.