EOLI XML

1
ESA plans for Catalogue and Order
Interoperability
Jolyon Martin ESA / ESRIN Earth Observation
Programme Ground Segment Department Jolyon.Martin_at_
esa.int
2
EOLI-XML

• A light simple stateless protocol for query of
  catalogues of EO products.
• Faithful to CEOS concepts of federated data
  providers
• A deviation from CIP/z39.50 in favour of ISO/OGC
• Successful as a technology proof of concept now
  ready for proposal as an interoperability standard

3
Motivation

• Modern technologies (web services)
• Programming interface suitable for
• End user clients
• Computer to computer processing (e.g. order
  verification and service chaining)
• Simple, intuitive interface
• Stateless protocol (does not require result set
  management)
• Easier interpretation / validation of protocol
• Cost Effective Solution
• Gateway development times on order of a month or
  less

4
Schemata

• Extensive analysis of standards and schemata used
  to define an XML, ISO 19115 compliant interface
  to ESA catalogue services,
• References ISO, GML, CIP, FGDC, OGC
• Prior experiences taken to account
• Satellite domain extensions defined
• Performance
• Efficient tag set
• Reference to browse URL data rather than binary
  data transfer in XML
• Readability
• Good, although ISO compliancy means a few tags
  are not at first intuitive and few tags are not
  so useful

5
Catalogue

• searchRequest this message allows to identify
  products inside a single collection via a search
  condition and to request the number of hits or
  product metadata in different formats as
  response.
• presentRequest this message allows to retrieve
  (multiple) product metadata within a single
  collection by providing the product
  identification.
• response this message contains the result in
  form of number of hits or returned product
  metadata.

6
searchRequest

• Simple search with hooks for provider specific
  conditions

7
presentRequest

• Retreives metadata from persistent product
  identifier

8
response

• Various formats for metadata results
• Brief (basic key metadata)
• Summary (brief thumbnail URL)
• Browse (brief plus browse URL)
• Full (the rest)

9
Catalogue Summary

• EOLI-Catalogue-XML
• Product search only
• NO collection search
• NO explain
• Focus on majority user requirements
• 15 pages of specification

• CIP
• Very rich feature set, but with high complexity
• gt 150 pages of specification

10
Order

• Adds order options presentation to response
• orderSubmitRequest
• orderMonitorRequest
• dataAccessRequest

11
orderOptions

• Full definition of processing, delivery options
• Simple scene selection mechanisms
• No business model for assumed submission
  (optional information URLs)
• (Too simple management of users)

12
orderSubmitRequest

• Changes in preparation, further simplifications
• Removal of packaging level
• Ordering of acquisition only
• Addition of programmingOptions
• orderSubmitRequest will renamed
  productOrderRequest and a simpler
  acquisitionOrderRequest to be added, ( many data
  are routinely delivered via subscription and do
  not require processingOptions, sceneSelection )

13
Order Summary

• Order-XML
• Still a slim specification (25 more) pages
• Simple interface for online acceptance of orders

• CIP
• Due to lack of take-up misses many features
  (future products, acquisition only, simple scene
  slection)
• Still complex interaction model

14
Overall Experiences

• Easy mapping of schema to various catalogue
• Performances are good (few noticable differences
  from EOLI via GIP and EOLI via XML)
• Some optimizations still possible (reduction in
  number of record formats?)

15
Take-Up

• EOLI-XML now THE catalogue interface in ESA
• MASS/SSE (Catalogue-XML First take up,
  successfully demonstrated inter-access and
  service chaining from Catalogue)
• EOLI-SA (Catalogue-XML Order-XML Next version
  4.0 will use just XML interface to MUIS)
• INFEO (Catalogue-XML CIP to XML Gateway has just
  passed FAT)
• ESA/MUIS, CNES/SPOT, RAL/ATSR catalogue
  interfaces are implemented KARI/Kompsat, IPT/EROS
  nearing completion.

16
ESA Plans

• Persue EOLI-Catalogue-XML as OGC minimal profile
  for Earth Observation
• Starting point for GMES preparation
  (Heterogeneous Mission Access)
• Propose the new standard towards CEOS
• In parallel - further develop a richer version to
  support ESA PI specialist requirements