Compare the difference between pervasive computing and other computings?

Answer 1

First, let's look at what they mean.

Ubiquitous means everywhere. Pervasive means "diffused throughout every part of." In computing terms, those seem like somewhat similar concepts. Ubiquitous computing would be everywhere, and pervasive computing would be in all parts of your life.

That might mean the difference between seeing kiosks on every street corner and finding that you could -- or need to -- use your Palm handheld to do absolutely every information-based task.

And, in fact, that's where the difference between these two types of computing lies. Pervasive computing involves devices like handhelds -- small, easy-to-use devices -- through which we'll be able to get information on anything and everything. That's the sort of thing that Web-enabled cell phones promise. Ubiquitous computing, though, eschews our having to use computers at all. Instead, it's computing in the background, with technology embedded in the things we already use. That might be a car navigation system that, by accessing satellite pictures, alerts us to a traffic jam ahead, or an oven that shuts off when our food is cooked.

Where IBM is a leader in the pervasive computing universe -- it has a whole division, aptly called the Pervasive Computing division, devoted to it -- Xerox started the ubiquitous thing back in 1988.

Ubiquitous computing "helped kick off the recent boom in mobile computing research," notes its inventor, Mark Weiser, who came out with the concept at Xerox's Palo Alto Research Center, "although it is not the same thing as mobile computing, nor a superset nor a subset." That means that people who use ubiquitous computing to mean computing anytime, anyplace -- to describe hordes on a street corner checking their stock prices until the "walk" light comes on or efforts to dole out laptops to all students on a college campus -- aren't using the rightterm.

We don't really need to use either one. I'd be happy to call pervasive computing mobile computing, and to call ubiquitous computing embedded or invisible or transparent computing -- or even just built-in functions.

Besides, until either ubiquitous or pervasive computing is anywhere and everywhere, those alternatives seem more accurate.