Troubleshooting cable modem
more from info
Jan 16, 09

I've been having issues with my cable modem, decided to do some digging. First, from within my home network, most cable modems will respond to this url:

http://192.168.100.1/

Mine has basic info, but I want to see Power and Signal-to-Noise Ratio (SNR), preferably both downstream and upstream. Quick Google showed me how to access the locked screens on my cable modem (WebSTAR DPC2100R2):

http://192.168.100.1/_aslvl.asp
set "Access Level 2"
login: admin
password: W2402

Then I could see Power and SNR numbers, for both downstream and upstream. If those numbers don't make sense to you, this is a good reference for cable modem signal levels.