Cyberinfrastructure to Meet Peak Demand for Emergency Data in Rural Areas

Published 03/21/2011

"San Diegans need somewhere to turn when a natural disaster hits a rural area nearby, in order to make better decisions about what to do next," said Hans-Werner Braun, a research scientist at the San Diego Supercomputer Center (SDSC) at UC San Diego, and director of the SDSC-based Applied Network Research group, which operates the High-Performance Wireless Research and Education Network (HPWREN). "Until now we have been able to provide that service covering large parts of San Diego's back-country, but we need to ensure that during the next crisis, peak demand for our data will not swamp our ability to keep the camera feeds up and running."

The UC San Diego division of the California Institute for Telecommunications and Information Technology (Calit2) and the National Science Foundation-funded HPWREN are partnering on the new project.

"Calit2 is enriching situational awareness in rural San Diego not just for those who live there, as well as their friends and family elsewhere, but also for emergency responders who need to know the situation on the ground before they arrive on the scene," said Calit2 director Larry Smarr. "HPWREN is a tremendous asset, and with Calit2 providing a more scalable data server architecture and backend with additional hardware, the network can serve the needs of many more people and agencies - not just during wildfires, but in other emergencies as well."

Approximately 1,000 people visit HPWREN's web page to view camera feeds on a typical day. On a not-so-typical day, like when snow recently blanketed large swathes of rural San Diego mountaintops, the number of visitors quadrupled. Braun compares that with what happened during the 2007 Harris Fire.

"We ended up at the peak with roughly 50,000 visitors in a single day, and they downloaded more than 70 gigabytes of data from a single server," he said. "Keep in mind that every page visit may return 30, 40 or 50 items, or 'hits', so those peak loads can overwhelm a server. It's very hard to optimize for a system that can jump up to 50 times normal daily users for brief periods of time - and you don't know which day the disaster will strike."

After HPWREN joined forces last October with the County of San Diego and Calit2 on the FireSight project to deploy new cameras on Mt. Woodson, Red Mountain (near Fallbrook) and elsewhere, it became clear that enhancing the camera network was not enough. It had to be able to withstand an onslaught of visitors to the website. Calit2 proposed to HPWREN's Braun that the institute dedicate server hardware from its NSF-funded GreenLight project to handle the peak loading. The project would also help GreenLight by providing another application type that can be tracked for its energy usage.

"We were able to spend significant GreenLight funds for this because of the opportunity for energy monitoring of at-scale, broad-interest services," noted Calit2's Tom Defanti, PI for Greenlight.

The solution devised by Calit2 engineers, including Greg Hidley, Brian Dunne, Joe Keefe and Chris Misleh, is fully scalable, and robust enough to handle any foreseeable response to wildfires or other visible hazards.

"The HPWREN and GreenLight teams developed a strategy to improve access to HPWREN camera data," said Hidley, chief engineer on the GreenLight project. "Our team put together an infrastructure upgrade implementation plan for this strategy designed to improve performance, control and reliability of HPWREN data access as well as provide improved infrastructure reliability and data redundancy."

Calit2 copies HPWREN content from HPWREN cameras via iRODS, a second-generation data grid system, to a Calit Sun Thumper, which then replicates it on three other Thumpers (two in Calit2's Atkinson Hall, and one in Project GreenLight's SunMD modular datacenter adjacent to the School of Pharmacy and Pharmaceutical Sciences).

All the Thumpers are running on the NSF-funded, Calit2-led OptIPuter ultra-broadband network linking major research buildings on the UC San Diego campus. Web servers have been set up on the Thumpers and the A10 load balancer was installed to distribute web requests across multiple servers. The new cyberinfrastructure should be able to respond to hundreds of thousands of visitors, and scale even higher on a moment's notice with the addition of new Thumpers.

For now, HPWREN will continue to host content on its original server, while the scalable server complex at Calit2 hosts a mirror site. "It's not just creating redundancy in the system or playing the role of backup, although that is part of it in the short run," said Braun. "Scalable servers are much better able to distribute the content, so over time the scalable system will eventually become the main site."

"We expect significant improvement in performance, especially during large-scale events," added Braun. "Eventually we look forward to integrating more environmental sensors, not just cameras, into the network. We could integrate various other kinds of environmental sensors to present a collated view of complex situations. Examples are water and air quality, meteorological data, and seismic data. Many such sensors are already in operation on HPWREN."

Media Contacts:
Doug Ramsey, Calit2 Communications
858-822-5825 or dramsey@ucsd.edu

Jan Zverina, SDSC Communications
858 534-5111 or jzverina@sdsc.edu

Warren R. Froelich, SDSC Communications
858 822-3622 or froelich@sdsc.edu

Related Links

HPWREN: http://hpwren.ucsd.edu
HPWREN Calit2 Camera Feeds: http://cameras.hpwren.optiputer.net
Applied Network Research: http://anr.ucsd.edu
Calit2: http://www.calit2.net
SDSC: http://www.sdsc.edu
HPWREN Harris Fire Videos http://hpwren.ucsd.edu/Fires/20071021-20071028_LP/index-full.html