Sensor Networks: Next Generation Problems

Frank VernonScripps Institution of OceanographyUniversity of California at San Diego

SAMSI Sensor Network Workshop14-15 October 2003

Open problems• How can I acquire desired RT data?• How can I discover/access desired RT data?• How can I share/integrate the data?• Can I integrate dynamically?• Can I share with other disciplines?• Can I integrate seamlessly with data from other

disciplines • Can I integrate with archived data?

Sensor Networks Desires• Timing

– Critical issue for any modal analysis or array processing analysis

– Need to synchronize across all sensors• Communications systems

– Power < 1W for remote sites– IP– Aggregate data rate ≥ 1 Mbit/sec– Scalable for array apertures from

100s meters => megameters

What is needed for a real-time data exchange systems:• System should be “data neutral”

– Variable packet size– All formatting at application level

• System should allow data query functions

• System should allow dynamic updates of instrument metadata

– metadata not embedded in every data packet • Packet descriptions should be available in real-time

– Self-describing

What is needed for a real-time data exchange systems:

• System should be network transparent with respect to read/write/local/remote access

• System should be error-free and robust – Impervious to communications failures– Impervious to computer shutdown-startup– Generally means non-volatile buffers, auto-

reconnects, auto-restarts, etc.• Interoperable with other real-time data exchange

systems and new real-time data sources

Design Goals for FutureReal-Time Sensor Networks

• capture, process, control for quality, and integrate real-time data streaming from different sources--collected for different purposes, on different time and spatial scales, and measured by different methods;

• make heterogeneities in platforms, physical location and naming of resources, data formats and data models, supported programming interfaces, and query languages transparent to the user;

• adapt to new and changing user requirements for data and data products;

Design Goals for FutureReal-Time Sensor Networks

• dynamically reconfigure with the addition or removal of observational equipment and/or scientific instrumentation– self-healing topology

– decentralized resource registration

• provide Internet access to integrated data collections along with visualization, data mining, analysis, and modeling capabilities