U.S. Department of the Interior U.S. Geological Survey Center of Excellence in Geospatial Information Science Functional Analysis for The National Map Server-side Computing Functional Analysis for The National Map Server-side Computing Eric B. Wolf, Scott Haefner, Michael P. Finn, and Barbara S. Poore 24 March 2009

Overview  What is The National Map?  Earthquakes!  Getting things to Cooperate  Tiles in the Cloud  What is The National Map?  Earthquakes!  Getting things to Cooperate  Tiles in the Cloud

What is The National Map? The descendant of the USGS Topographic Map Series  7.5’ 1:24,000 “Quad Sheets”  ~55,000 unique sheets covering the US and Territories  Started in mid 1940s  “Completed” in 1992 The descendant of the USGS Topographic Map Series  7.5’ 1:24,000 “Quad Sheets”  ~55,000 unique sheets covering the US and Territories  Started in mid 1940s  “Completed” in 1992

What is The National Map? Eight Data Layers:  Place Names (GNIS)  Structures  Transportation  Boundaries Eight Data Layers:  Place Names (GNIS)  Structures  Transportation  Boundaries  Hydrography (NHD)  Elevation (NED)  Land Cover  Othroimagery  Hydrography (NHD)  Elevation (NED)  Land Cover  Othroimagery

What is The National Map? Many uses including:  Recreational  Scientific Analysis  Emergency Response Essentially a “basemap” for many purposes. Many uses including:  Recreational  Scientific Analysis  Emergency Response Essentially a “basemap” for many purposes.

Earthquakes Images of websites from: June 24, 1997 March 3, 2009

Earthquakes  Earthquake site sees about 250,000 “hits” per second after an earthquake  USGS network can’t handle the load  Static files are easy to “cache”  Static file caching on  Earthquake site sees about 250,000 “hits” per second after an earthquake  USGS network can’t handle the load  Static files are easy to “cache”  Static file caching on

WMS Mashup World Wide Web World Wide Web WMS Basemap GeoRSS Feed Real-time Earthquakes GeoRSS Feed Real-time Earthquakes OpenLayers

TileCache Mashup World Wide Web World Wide Web WTMS Basemap GeoRSS Feed Real-time Earthquakes GeoRSS Feed Real-time Earthquakes OpenLayers

Tiles in the Cloud  What if the default symbology does not work?  What if you need to combine more data layers?  How can you build a dynamic mapping system that can handle 250,000 hits/second?  How can you build it before people start dying?  What if the default symbology does not work?  What if you need to combine more data layers?  How can you build a dynamic mapping system that can handle 250,000 hits/second?  How can you build it before people start dying?

OpenLayers + Geoprocessing AWS Public Data Store EC2 Instance hosting custom cache EC2 Instances Grid TileCache (temporary) EC2 Instances Grid TileCache (temporary)

Thank you!