Hurricane Sandy Broke Only 10 Percent of New York Area’s Internet

A natural disaster like Hurricane Sandy is one of those situations in which the people who keep track of the mysterious and complicated underpinnings of the Internet have some surprisingly interesting observations to make. So it is with the folks at the research firm Renesys, which monitors the overall health of the Internet by watching which networks are up and which are down.

Naturally, there has been a lot of activity in their world during the last 48 hours or so, as Hurricane Sandy rumbled through the area, flooding data centers and central offices in Manhattan, among other things.

I’m a pretty technical guy and even I don’t know what a routing table is. But the video below is a time-lapse view of groups of different networks going offline as the storm passes. As Renesys explains in this blog post, the greenest of the green squares indicate that more than 99.95 percent of networks in a given area are running. The red ones indicate that more than 5 percent of the networks in the area have been knocked offline.

When you consider the density of the urban environments of lower Manhattan, coastal New Jersey, Connecticut, Brooklyn, Queens and Long Island, and realize that network density necessarily coincides with population density, it’s pretty jarring to see this much of the Internet knocked offline, and it gives you a sense of the scale of the problems facing the people paid to keep the bits flowing.

Renesys concludes that about 10 percent of the networks in the New York metropolitan area went down, which is really low given the fact that the local electric company, ConEdison, actually cut power to the lower portions of Manhattan, where a lot of those networks are based.

It also says something good about the planning of those whose networks stayed up and running, and those who keep the backup generators running and who aren’t getting much sleep.

Even so, in the grander scheme of things, it’s still a lot: Renesys compares the impact of the networks that went down to that of an entire country the size of Austria going down. It is something we’ve seen before. Case in point: Egypt.

Renesys also says that the uptime and downtime of networks in a storm zone are becoming a helpful indicator for generalized storm damage assessment, too. If you know a network has gone down in a certain area, then there’s a pretty good chance that it has been hit by flooding or other storm damage, usually within seconds of the catastrophe occurring.

Renesys made a short video showing the damage over Oct. 29 and 30.