I mentioned the other day that I had run into Feng Zhao, principal researcher in the Networked Embedded Computing group, who was looking particularly happy at the moment. Well, Feng has been demonstrating the reason for his delight over the past three days: a set of small, wireless sensor devices, branded with the Microsoft Research logo, that he and his group plan to utilize in a variety of settings.

"This is an example of a sensor that we use for research and we plan to put into a data center," Zhao says, holding one of the devices up for inspection. "The sensors currently in data centers are a different form factor. This one just got designed. It senses temperature and humidity, the kinds of parameters one cares about in a data center."

The sensors are special, Zhao says, because of their size, their functionality, and their energy efficiency.

"We're working on making sensors easier to manage and interoperable with other devices," he says, "and to make the devices speak the kinds of language and protocols that computers on the Internet speak. For example, on the Internet, computers talk in terms of Web services, TCP/IP, HTTP. But these are designed for much bigger machines, and this one only has 4K of memory. We want to shrink these very big things onto this device with a very small memory and processor, and, furthermore, use as little energy as possible: two AA batteries for a year."

It's part of a research project called Tiny Web Services, designed to develop sensor nets and Web-service techniques that can fit onto these tiny 4K sensors. The sensors are programmed to go to sleep when not needed to send information.

"Web servers anticipate a set of requests, and they have to respond immediately," Zhao explains, "so they stay on all the time, waiting for requests. This one uses AC currency, and Web services can register events to make it turn itself on. A number of these techniques are being used to make the footprint of Web-service processing much smaller and simpler but still comply with the standards of the Internet so the device can talk to other devices."

Zhao's group is one of the first to address this area, and its devices are among the smallest--and least expensive--to talk in terms Web services can understand. Beyond their small footprint, they also contain technology that is advancing the state of the art.

"By building our own devices," Zhao says, "we actually are building a stack of software. We own all the drivers, and we can program. Our goal is to develop this into a reliable system, and we're also interested in making them available to academics, to help people building applications for the environment, for conservation, or for energy savings. If you look at what's currently available, some of those devices are not as reliable or as easy to program as we'd like." 

 With that, he was smiling again. These days, it seems, Feng Zhao just can't help himself.

Rick Rashid, senior vice president of Microsoft Research, shows one of Feng Zhao's new wireless sensors to an audience of invited guests during Tuesday's TechFest keynote speech.