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Edwin Wisse & Rob van Swol |
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National Aerospace Laboratory |
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History: Sawa and SatCAST demonstrations |
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Neonet network |
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The software |
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Metadata gathering and distribution |
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Using multicast to distribute metadata |
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Demonstration |
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Demonstrated IP over satellite & caching, no
multicast |
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Application: Neonet version 0 |
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No XML yet: HTML based |
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Built a single site combining and crosslinking
pages from different sites about a common theme: remote sensing |
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Site was replicated on different UNEP sites by
retrieving databases with HTML files. |
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Multicast capability |
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Demonstration application: Neonet version 2 |
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Using structured metadata in XML |
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Network with nodes about different topics in
remote sensing |
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Demonstration: |
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Neonet functionality |
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Database synchronisation by multicast over
satellite link. |
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Netherlands Earth Observation Network |
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Allow (Dutch) users of remote sensing data
access to information in the Netherlands and abroad. |
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Keep information at the provider |
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Connect to other metadata infrastructures |
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CEOS IDN |
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CEO |
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The network is a group of nodes running Neonet
software |
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Node maintainer(s) decide what is appropiate
information |
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A node servers a user community, example: |
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atmospheric chemistry |
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water management |
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Nodes are organised hierarchically |
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General node at top: APEX |
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Retrieve metadata from provider by HTTP |
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Version 0: HTML pages |
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Version 1: metadata in XML pages (CEO like
format) |
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Uses CEO standard for metadata |
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Status: version 2 released october (but used in
SatCAST) |
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Available for interested institutes |
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3 top level nodes with local databases and no
sub-nodes |
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Synchronisation: |
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Nodes synchronise their databases using HTTP
requests |
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Added for SatCAST |
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Multicast aspect: |
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New or changed XML files get broadcasted to all
nodes |
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Nodes retrieves files and records from local
cache |
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No multicast for servlet results, only for
database synchronisation |
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Three nodes were set up, all are Apex nodes. |
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Check each other every 10 minutes. |
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Metadata entered at 1 node is found and
retrieved by the others |
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No instant result |
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Short demonstration of other Neonet features |
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Questions? |
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Notes