It is very useful to know the DOCSIS cable modems signal levels, as detailed in this FAQ:
How to access signal levels on my cable modem?However, it is very common that the default cable modem IP address for statistics is not accessible if you are behind a Wi-Fi Router. We will detail the steps to connect to your cable modem even behind your Wi-Fi below. This assumes some knowledge of networking and IP addresses.
1. Connect to the admin interface of your Wi-Fi router - you will need to know the router IP, admin username/password. It is often at
192.168.1.1, or you can lookup defaults in our hardware database with nearly 5000 routers/modems.
In the Wi-Fi routers admin interface, navigate to LAN settings, and look for setting up a "static route".
2. Add a static route to the cable modem's diagnostic IP - this is usually located in the "LAN" section of routers' settings.
The "static route" settings you'll need to add are as follows:
IP address: 192.168.100.1 (the IP of the cable modem's stats page, or ISP router admin page)
Netmask: 255.255.255.255
Gateway: 192.168.1.1 (or the IP of your Wi-Fi router)
Interface: WAN
2a. Alternatively, connect a client device directly to the cable modem - if the above steps don't work for you, or seem too complicated, you can connect a PC/Laptop directly to the cable modem with an Ethernet cable. Note that you'd likely have to reboot the cable modem to recognize the new device connected to it.
See Also:What cable modem signal levels are considered good?
