Data Services Newsletter

Volume 7 : No 2 : June 2005

Web Services at the IRIS DMC

Notice: All web services are now provided via the new services interface at http://service.iris.edu

- IRIS DMC Webmaster, 2013-08-08

Leading in new technology

IRIS has always been a leader in advancing the use of enabling technologies within the seismological community, including the development and adoption of a comprehensive data file format and tools, web browser-based access mechanisms, distributed archive access, and CORBA-based programmatic interfaces into the archive. The IRIS Data Management Center continues in that role with the development of web services-based interfaces and services.

Why web services?

Distributed computing is a complex problem, with no single one size fits all solution. When choosing a technology to support distributed computing, many different aspects must be considered. Web services provide some unique features, making them important components in the services offered by IRIS.

The most important feature of web services is the ability to use the http communication protocol, and therefore communicate in the presence of all but the most restrictive firewalls. Many system administrators have responded to the onslaught of malicious viruses by shutting off access on most internet communication ports, except that used by web browsers (port 80). By running on the same port as common web browsers, web services can be accessed by anyone with web access.

Web services are also becoming a ubiquitous tool, with support in many programming languages and scripts. Scientific users can access data supplied through web services from within MATLAB, Java or C, while web developers can use Flash or Perl. Web service clients don’t require advanced programming skills to successfully implement.

Web service projects at the DMC

Current efforts at the DMC include a web service front-end to the CORBA-based Data Handling Interface (DHI-WS), a framework to support time series processing (seismoproc), and the Uniform Product Distribution System (UPDS). The DHI-WS service provides a subset of the DHI interface to provide the commonly accessed DHI functionality to clients behind firewalls. Seismoproc enables the publishing of seismic data processing algorithm implementations for use by external client applications. UPDS will provide a coherent web services-based system to manage the submission, searching, and access of USArray XML-based Data- and Informational Products.

The DMC strives to provide tools and services that best fit the needs of the community. Given the flexibility and ease-of-use that web services offer, we feel that web services are the components on which a broader community-oriented service framework can be built.

Web services schematic
Figure 1: Web services schematic showing simplified access to services.

A client invokes the services of a remote web services-based server using standard http calls across the Internet.

by Joanna Muench and Linus Kamb (IRIS Data Management Center)

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