The IRIS Federator: Accessing Seismological Data Across Data Centers

Abstract:

In 2013 the International Federation of Digital Seismograph Networks (FDSN) approved a specification for web service interfaces for accessing seismological station metadata, time series and event parameters. Since then, a number of seismological data centers have implemented FDSN service interfaces, with more implementations in development. We have developed a new system called the IRIS Federator which leverages this standardization and provides the scientific community with a service for easy discovery and access of seismological data across FDSN data centers. These centers are located throughout the world and this work represents one model of a system for data collection across geographic and political boundaries.

The main components of the IRIS Federator are a catalog of time series metadata holdings at each data center and a web service interface for searching the catalog. The service interface is designed to support client­-side federated data access, a model in which the client (software run by the user) queries the catalog and then collects the data from each identified center. By default the results are returned in a format suitable for direct submission to those web services, but could also be formatted in a simple text format for general data discovery purposes. The interface will remove any duplication of time series channels between data centers according to a set of business rules by default, however a user may request results with all duplicate time series entries included. We will demonstrate how client­-side federation is being incorporated into some of the DMC’s data access tools. We anticipate further enhancement of the IRIS Federator to improve data discovery in various scenarios and to improve usefulness to communities beyond seismology.

Data centers with FDSN web services: http://www.fdsn.org/webservices/

The IRIS Federator query interface: http://service.iris.edu/irisws/fedcatalog/1/