Queries over Sensor Networks

Sam Madden

UC Berkeley Database Seminar

October 5, 2001

Sensor Environment Recent Research at UCB, MIT, UCLA focused

on hardware, systems, and networking issues in sensors

Database researchers conspicuously absent Lots of data challenges

• Streaming data• Intermittent connectivity• Power / Bandwidth Limitations• No Storage• Very limited code space, RAM

Fjords Sensors push data Want to combine that

data with pre-existing tables Traffic Example

Fjords abstract push/pull into connection between operators Bracket Model (Graefe)

Revisted

Continuous Queries

Sensor environments involve lots of queries over same set of sensors E.g. Building information system,

environmental / scientific monitoring Opportunity for Continuous Queries

Improve on existing approaches with adaptivity, support for streams

Aggregation in Sensor Networks

Push aggregates down into sensor networks to reduce data, power load on sensors

Take advantage of network topology

See Next Week’s DB Seminar