Saturday, September 19, 2009

Traffic congestion

Part of our moving to Redlands is to get used to dollars, ounces, gallons, and miles. Just when we thought we missed out on the change to the Euro, we find ourselves in conversions of our own. Fortunately, one thing has not changed upon moving to the Los Angeles basin: driving a car often means: follow the red lights in front of you…

Another stable factor so far has been the use of Internet. We still use the same free e-mail provider as we did when we lived in the Netherlands. We only use it more often and with more people than before.

There is a kind of analogy between the road network and the Internet. First of all, the Internet and roads are collections of connected networks that allow transport between two locations. The networks may differ in type or size. Through agreed standards it has become possible to have objects pass from one computer network to another, thereby allowing the object to travel further than the limits of the originating network. And similarly, when traveling through Europe, I never had to change tires when crossing the border between two countries.

Just as is the case with the Internet, bandwidth is important on the road network. Bandwidth on a sandy forest road is much smaller than on a 4-lane interstate. And people using both types of networks share a preference for high bandwidth.

The increase in network traffic is the source of the third analogy between roads and Internet: traffic congestion. No matter the size of your driveway or the horsepower of the engine of your car, you will get into a traffic jam just as you turn on the highway. And similarly it doesn’t seem to help to have a cable modem installed to surf the web when everybody else does the same and uses it at the same moment you do.

So, now we have seen that the two types of networks are similar and share the same problems, can we benefit from this knowledge? Perhaps we can. Over the past years we have been building more roads, thereby increasing the bandwidth. This was not enough to meet the increasing demands due to the need or desire to travel.

With Internet traffic a different development can be observed. In the early nineties the Internet was accessed through a 9600 bps modem, the happy few having access to a 14.4 kbps one. Since then data volumes have increased exponentially, now allowing us to serve GIS data and functionality over the Internet.

Apparently we have found some solutions that help to minimize traffic congestion on the Internet. Whether it is data compression (car-pooling), or the use of high bandwidth backbones in addition to low-speed home phone lines (treating local traffic differently from long-distance traffic), there should be something we can learn from Internet developments when designing new road plans or addressing traffic problems in our GIS consulting work. Indeed we already apply some form of packaging (as is done with information sent over the Internet) with the introduction of traffic information systems that guide us along a route that has the least chance of jams!

I do not pretend to have the solution to traffic congestion problems. But we tend to keep following a familiar line of thought in solving geographic problems, and that has not always helped us find a more permanent solution. Sometimes the solution to a problem is found in an unexpected location or at an unexpected moment. So be sure to always bring your notepad and pencil, wherever you go, just to make sure you don’t miss that one leap of mind.

Appeared in GeoInformatics Magazine ( in April/May 2002

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