To make such networks workable, novel wireless protocols quite distinct from the familiar ones that are the basis of conventional wireless applications such as WiFi are required. “WiFi,” says Heidemann, “is not applicable because it requires all the nodes to be listening all the time.”
Creating specialized sensor protocols has been a high priority since the inception of sensor networks. More than three years of recent ISI research spearheaded by ISI’s Dr.Ye – supported by the National Science Foundation, Intel and other funders – produced a new protocol, SCP-MAC, which marked a major step forward. Among the advances made by SCP-MAC was a dramatic improvement in energy efficiency. Previous models required individual units to be active for approximately 2-3 percent of monitoring time – that is, active about 29-45 minutes of every day of sensornet activity. SCP-MAC reduced the monitoring time to fewer than two minutes out of each day.
For scientific research, sensornets are now going into wider use. NEON, an NSF Major Research Facilities and Construction Project that might reach $200 million in funding, is planned as a continental-size sensor network designed to study the effects that land-use and meteorological changes have on the environment. Hundreds of sensors will be deployed over dozens of sites to measure changes in the air, soil, and water in wild lands and other locations throughout the country.
Another ISI project, under the leadership of Aaron Falk, will permit accelerated, easy access to the more efficiently collected NEON wireless sensornet data. Falk is creating a Satellite Sensornet Gateway (SSG) system, which in essence will be a communication chain originating at the local sensornet, then transmitting data from the network to a satellite or other wireless network. This SSG, according to Falk, “won’t just collect and store data. Instead, it will all process it to make it easily and transparently accessible anywhere. Moreover, the processing won’t just be a single, pre-set mode, but will be programmable to supply the specific mix of data the investigators are looking for.”
SSG technologies might at some point handle data from an ISI initiative that is part of research taking place at the USC Center for Interactive Smart Oilfield Technology, funded by Chevron and other industry representatives. Heidemann, Ye and others from the ISI are working on ways to use sensornets to monitor oil operations, both conventional land-based and new deepwater fields now being developed in the Gulf of Mexico and elsewhere.
“The earliest applications for many technologies have long been military and scientific….”
By Herbert Schorr
Executive Director
USC Information Sciences Institute
