Monitoring a cable modem

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Some time ago I was having an issue with my cable modem connection.  The connection was intermittent at certain times of day but fine otherwise.  Calling the cable company with an intermittent problem is pointless: you get the standard answer “But it’s working fine now”.

So, since I have the world’s smartest home automation system running in my closet it was trivial to add a quick HTML scraper to read the cable modem statistics every few minutes, persist them to storage and then add some graphs showing how they vary over time.

The .NET Chart Control is what I’m using now to render these charts.  I’ve tried Google charts, Open Flash Charts and even my own pure-CSS chart generator.  The .NET Chart control has the best options at the moment and it’s a plain JPG file so it will work on any browser.

After a few days I had a better picture as to how the signal strength and signal to noise ratio was varying over time and was quickly able to realize that it was in fact weather related.  Waterproofing the cable connections cured the problem.