Monitoring ADSL Drop OutsNov18

At home we have previously had issues with our ADSL dropping out intermittently and have had the ISP send technicians around to fiddle test and rewire etc. This seemed to make a difference for a good while, but as of the last two days we are back to square one with frequent and annoying ADSL disconnections (no changes to anything in the house).

What I’m afraid of doing now is ringing the ISP again and being told the standard “restart the router”, “pull all the phones out of the wall”, “turn the oven off”/”Pray to the Gods” etc etc, all of which I know most likely has nothing to do with it (tried it all before).

I decided to do my own internet research for reasons why ADSL might drop out. I learnt all sorts of interesting things about noise margin’s, line attenuation, data sync rates etc that all have an impact on how stable the line is.

Checking my Belkin router’s status page, I note that it actually gives me this information - cool:

Of course, I start rapidly refreshing the page to see how the numbers are changing as the ADSL internet connection drops in and out. The Data rate is different on each reconnect, and the noise margin is fluctuating all over the place.

Refreshing is no good, tonight I decided that this goodness needed to be graphed!

Window’s inbuilt performance counters are ideal for this sort of thing. We just need a custom performance counter for the ADSL connection data, poll the router’s status page and feed the new performance counter with data.

I fired up Visual Studio and started plugging away at a windows app that will do this for me – easy to do – behold the ADSL Monitor:

The following code creates the new ADSL performance object, with the four counters I’m interested in (noise margin up/down and data rate up/down):

CounterCreationDataCollection counters = new CounterCreationDataCollection();

counters.Add(new CounterCreationData("Noise Margin Down", "Noise Margin Down", PerformanceCounterType.NumberOfItems64));
counters.Add(new CounterCreationData("Noise Margin Up", "Noise Margin Up", PerformanceCounterType.NumberOfItems64));
counters.Add(new CounterCreationData("Data Rate Down", "Data Rate Down", PerformanceCounterType.NumberOfItems64));
counters.Add(new CounterCreationData("Data Rate Up", "Data Rate Up", PerformanceCounterType.NumberOfItems64));

string _performanceCategory = "ADSL"; 

if (PerformanceCounterCategory.Exists(_performanceCategory))
{
PerformanceCounterCategory.Delete(_performanceCategory); 
}

PerformanceCounterCategory.Create(_performanceCategory, "ADSL Diagnostics", PerformanceCounterCategoryType.SingleInstance, counters);

I then fire off a thread and have it looping over the following every second:

	           
	while (running)
	{
		WebRequest request = WebRequest.Create("http://192.168.2.1/status.stm");
		WebResponse webResponse = request.GetResponse();
		StreamReader stream = new StreamReader(webResponse.GetResponseStream());
		string statusPage = stream.ReadToEnd();
		stream.Close();
		webResponse.Close();

		//Providing data to the performance counter 
		PerformanceCounter pc = new PerformanceCounter(_performanceCategory, "Noise Margin Down", false);
		pc.RawValue = Convert.ToInt32(GetDataResult(DataMatch.adsl_noise_margin_ds, statusPage));
		...

		Thread.Sleep(1000); 
	}

A simple Regex is used in GetDataResult to pull the appropriate data off the router’s status page.

Now, browsing to the inbuilt windows Performance Monitor, we can add our newly created ADSL performance object and graph what is really going on. For me, it was looking like this:

What the ! !  It seems more than half the time I’m without internet. The most important lines I believe are the blue and red. The blue shows the synced data downstream rate (higher the better), and the red shows the downstream noise margin (once again, higher the better – apparently anything below 6 is quite unstable).

Where the blue line is at rock bottom is where I don’t have any internet at all. What a pain – as you can see towards the end it started to stabilise with quite a high noise margin, albeit a low data rate :(
This will hopefully give me more information to provide the ISP however when I finally do ring as well as letting me monitor the situation and not even bother surfing the internet while it is ridiculously unstable. 

Sigh.