HR: 1330h
AN: S52C-0152    [PDF]
TI: Circuit-Detour Design and Implementation - Enhancing the Southern California's Seismic Network Reliability through Redundant Network Paths
AU: * Watkins, M
EM: watkins@gps.caltech.edu
AF: Caltech, 1200 E. California Blvd. Seismo Lab - MC 252-21, Pasadena, CA 91125 United States
AU: Busby, R
EM: rbusby@chanzseis.com
AF: Channel Z Seismometry, 37 Haynes Avenue, Falmouth, MA 02540 United States
AU: Rico, H
EM: hugo@gps.caltech.edu
AF: Caltech, 1200 E. California Blvd. Seismo Lab - MC 252-21, Pasadena, CA 91125 United States
AU: Johnson, M
EM: mandy@gps.caltech.edu
AF: Caltech, 1200 E. California Blvd. Seismo Lab - MC 252-21, Pasadena, CA 91125 United States
AU: Hauksson, E
EM: hauksson@gps.caltech.edu
AF: Caltech, 1200 E. California Blvd. Seismo Lab - MC 252-21, Pasadena, CA 91125 United States
AB: We provide enhanced network robustness by apportioning redundant data communications paths for seismic stations in the field. By providing for more than one telemetry route, either physical or logical, network operators can improve availability of seismic data while experiencing occasional network outages, and also during the loss of key gateway interfaces such as a router or central processor. This is especially important for seismic stations in sparsely populated regions where a loss of a single site may result in a significant gap in the network's monitoring capability. A number of challenges arise in the application of a circuit-detour mechanism. One requirement is that it fits well within the existing framework of our real-time system processing. It is also necessary to craft a system that is not needlessly complex to maintain or implement, particularly during a crisis. The method that we use for circuit-detours does not require the reconfiguration of dataloggers or communications equipment in the field. Remote network configurations remain static, changes are only required at the central site. We have implemented standardized procedures to detour circuits on similar transport mediums, such as virtual circuits on the same leased line; as well as physically different communications pathways, such as a microwave link backed up by a leased line. The lessons learned from these improvements in reliability, and optimization efforts could be applied to other real-time seismic networks. A fundamental tenant of most seismic networks is that they are reliable and have a high percentage of real-time data availability. A reasonable way to achieve these expectations is to provide alternate means of delivering data to the central processing sites, with a simple method for utilizing these alternate paths.
DE: 7200 SEISMOLOGY
DE: 7212 Earthquake ground motions and engineering
DE: 7223 Seismic hazard assessment and prediction
DE: 7294 Instruments and techniques
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: 2003 Fall Meeting