NetDC

TECHNICAL MANUAL for NETWORKED
DATA CENTERS (NetDC) PROTOCOL

Robert Casey and Tim Ahern
IRIS Data Management Center
Seattle, Washington

• 0.0 INTRODUCTION
• 1.0 OVERALL CONCEPT
• 2.0 NETDC REQUEST FORMAT
• 3.0 REQUEST RECEPTION AND DELEGATION
• 4.0 NETDC DATAGRAMS
• 5.0 LOCAL REQUEST PROCESSING
• 6.0 INVENTORY (.INV) REQUESTS
• 7.0 RESPONSE (.RESP) REQUESTS
• 8.0 WAVEFORM (.DATA) REQUESTS
• 9.0 PRODUCT SHIPMENT
• 10.0 NETDC INSTALLATION AND SETUP
• 11.0 WRITING YOUR INTERFACE CODE
• 12.0 GENERAL HOUSEKEEPING AND TROUBLESHOOTING
• 13.0 FUTURE IMPLEMENTATIONS
• 14.0 CONCLUSION
• APPENDIX A - SUMMARY OF NETDC DATAGRAMS

In recent years, we have seen the Internet flourish as a medium for the exchange of ideas and data. This has helped scientific research reach new heights of cooperation and discovery as institutions have begun to find critical data for their studies readily available in a form they can quickly put to use. Advances in the seismic research arena have been no exception.

There are currently many seismological data centers scattered about the globe providing services that make seismic data available to researchers. Each center tends to focus on a subset of the worldwide collection of data. With so many data centers out there, a scientist looking for data has to be aware of whom to contact and how to request the data, the latter case tending to vary widely from data center to data center. This paradoxically leads to a situation where there is a massive amount of data within reach that few know how to find and extract.

One solution to this problem is to unify these various data centers to appear like one large data center. By providing a single, common request interface the user is able to submit a data request without the need to know the specifics of how their request will be fulfilled. The worldwide network of data centers then becomes an integrated archive of data holdings, virtually eliminating the need for each data center to "mirror" other sites just to make the data readily available to its customer base.

This solution takes the form of Networked Data Centers: A set of utilities and protocols that interconnect data centers and provide a means of exchanging and merging data for user collection. The system is entirely automated in its networking procedures and provides an avenue for data centers to increase their customer base and data production volume.

This technical manual outlines the concepts of Networked Data Centers and provides specifics for installation, maintenance, and use of this software system.

introduction •• overall concept •• request format •• request reception and delegation
datagrams •• local request processing •• inventory requests •• response requests
waveform requests •• product shipment •• installation and setup •• writing interface code
troubleshooting •• future implementations •• conclusion •• appendix A - summary of NetDC datagrams