1. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-1A Edwin Wisse & Rob van Swol National Aerospace Laboratory Neonet A metadata application demonstrating SatCAST

2. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-2A Overview l History: Sawa and SatCAST demonstrations l Neonet network l The software l Metadata gathering and distribution l Using multicast to distribute metadata l Demonstration

3. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-3A 1998: Sawa demonstration l Demonstrated IP over satellite & caching, no multicast l Application: Neonet version 0 l No XML yet: HTML based l Built a single site combining and crosslinking pages from different sites about a common theme: remote sensing l Site was replicated on different UNEP sites by retrieving databases with HTML files.

4. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-4A 2000: SatCAST demonstration l Multicast capability l Demonstration application: Neonet version 2 l Using structured metadata in XML l Network with nodes about different topics in remote sensing l Demonstration: –Neonet functionality –Database synchronisation by multicast over satellite link.

5. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-5A Neonet: Background l Netherlands Earth Observation Network l Allow (Dutch) users of remote sensing data access to information in the Netherlands and abroad. l Keep information at the provider l Connect to other metadata infrastructures –CEOS IDN –CEO

6. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-6A Neonet nodes A Neonet node is a website with supporting software. A node covers a self-chosen theme in remote sensing Users can search for and enter metadata in a fixed format. Format is derived from the CEO recommendation on metadata.

7. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-7A Neonet network (1) l The network is a group of nodes running Neonet software l Node maintainer(s) decide what is appropiate information l A node servers a user community, example: –atmospheric chemistry –water management l Nodes are organised hierarchically l General node at top: APEX

8. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-8A Neonet network (2)

9. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-9A Metadata flow Node Provider metadata file Node email Metadata entered at a specialised node is sent automatically to the nodes above. E-mail is available everywhere Even behind firewalls

10. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-10A Neonet software l Retrieve metadata from provider by HTTP –Version 0: HTML pages –Version 1: metadata in XML pages (CEO like format) l Uses CEO standard for metadata l Status: version 2 released october (but used in SatCAST) Available for interested institutes Available for interested institutes

11. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-11A Software: elements A Neonet node runs: Webserver Database Servlet package Java application for database sync and metadata retrieval Nodes can be installed on systems running Windows and a number of Unix systems (SGI, Solaris, Linux).

12. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-12A SatCAST setup l 3 top level nodes with local databases and no sub-nodes l Synchronisation: –Nodes synchronise their databases using HTTP requests –Added for SatCAST l Multicast aspect: –New or changed XML files get broadcasted to all nodes –Nodes retrieves files and records from local cache –No multicast for servlet results, only for database synchronisation

13. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-13A Synchronisation Node XML admin Node XML admin SatCAST Multicast Node A node exports its database to a set of XML files, so it can be accessed using HTTP

14. Nationaal Lucht- en Ruimtevaartlaboratorium National Aerospace Laboratory NLR CXXX-14A Demonstration l Three nodes were set up, all are Apex nodes. l Check each other every 10 minutes. l Metadata entered at 1 node is found and retrieved by the others l No instant result l Short demonstration of other Neonet features l Questions?