The MacAlba

I’d noticed that the network link between home and the world had died at around 1pm (localtime) for the past few days. Then yesterday, Saturday, I happened to glance at the Gilat SkyEdge IP satellite modem at a telling time. The signal level was way down. The first thing that crossed my mind was that the strong wind blowing at the time had nudged the satellite dish a little. Then, just as I was musing over the problem, the signal strength started to rise, slowly and steadily. A few seconds later I realised that, given the time of day (midday if you ignore daylight savings), the sun would be behind the Optus satellite used by BorderNET.

A quick trip to Google confirmed that March and September (equinox time) were the times of the year that sun transit outages occur.

Today, I manually recorded signal strength (in dB) against time. Here’s the graph showing the results.

(click to enlarge)

It clearly shows that the carrier to noise ratio drops enough to make the signal useless for several minutes.

Sadly, from a customer service perspective and as best I can determine, BorderNET didn’t notify customers of such outages. I mentioned my lunchtime network loss to a BorderNET service desk operator on Saturday - he didn’t mention the possibility of sun transit outages. Neither is there a message on the BorderNET bulletin-board which expressly states that its purpose is to notify users of outages.

Anyway, it was interesting to experience this phenomenon firsthand.