1. U.S. Department of the Interior U.S. Geological Survey StreamStats: System Design and Web Implementation 12/18/02 Jacque Coles - USGS Dean Djokic - ESRI

2. System Design – Core Concepts (1) Client (IE 5.5) Web Server (IIS, ASP) Map Server (ArcIMS) Application Server (ArcMap, NFF) Data Server (ArcSDE) Database (SQL Server) Client (IE 5.5) Client (IE 5.5)

3. Web, Application, Map, and Data Servers are separate machines (but could be combined depending on the load and performance requirements). Current design is based on Windows platform. Scalability for Application Servers is accomplished by adding more physical servers (computers) with ArcGIS on them. System Design – Core Concepts (2)

4. Processing Roles (1) Web Client requests map activity (zoom in/out, delineation at a point, etc.) The request is sent to the Web Server.  If the request is one for standard map operations, it is forwarded to the Map Server  If the request is for watershed delineation/NFF computations, it is forwarded to the Application Server Web Server maintains connection between the client and the Map and Application Servers. WS DS MS AS

5. Application Server performs watershed delineation and characteristics extraction (ArcGIS) and flood frequency computations (NFF). The results are stored in the database through the Data Server (ArcSDE).  Communication between the Web and Application Servers is through a dedicated socket port. Processing Roles (2) AS DS MS WS

6. Processing Roles (3) Map Server (ArcIMS) manages standard internet- based mapping activities (zooming, panning, turning layers on and off, etc.). Data for map- based operations reside in the database accessible through the Data Server (ArcSDE).  Application and Map Servers do not communicate directly, but they do share the same database. “Communication” between the two is via Web Server. MS DS AS WS

7. Data Server (ArcSDE) stores the data for the Application Server and serves the data to the Map Server. Processing Roles (4) DS MS AS WS

8. USGS Streamstats Hardware Web Server  Dell PowerEdge 1650 Pentium III, 1.26GHz Single Processor  512MB SDRAM  Two 36GB SCSI 160 Drives  RAID 1 Application Server  Dell PowerEdge 2500 Pentium III, 1GHz Dual Processors  1GB SDRAM  6x36GB SCSI U3/160 Hard Drives  Tape Backup  RAID 5

9. USGS Streamstats Configuration App. Server Internet Web Server Request to IMS Response from IMS Request to ArcMap Response from ArcMap ArcMap ArcSDE SQL Server Data, NFF IIS, ASP ArcIMS

10. Communication Between Server Applications ASP routes requests to either IMS or Application server IMS handles map related requests – ZI,ZO,Pan Application server handles application specific requests Application server has an open port for ASP to communicate with ArcMap  Deliniation – polygon returned to IMS for Web viewer  GetParameters – parameters related to topographic and hydrologic data returned to IMS for Web viewer

11. Communication Between Server Applications (2) Programming was done by ESRI Denver and Redlands ASP, VB, ArcIMS and ArcObjects on server side JavaScript and DHTML on the client side Salmon and Clearwater basins (25,000 sq. mi. – 18 cataloging units) to be implemented by the end of January on the Idaho servers for restricted use