Clearinghouse Status

CAP Mid Year Meeting

Portland, OR 

May 18, 1999

Overview
        - Metadata prospects
        - Isite software status
        - Review of Isite installation
        - Commercial Solutions
        - Clearinghouse Interface Overview
        - Hosting your own search form
        - Clearinghouse and OpenGIS

ISO Metadata Prospects
        - Metadata relation element (parent/child) with inheritance in ISO 15046-15 - collection approach
        - Extent is the footprint dLat x dLong in square degrees
        - Metadata can be documented as to polygon footprint and made searchable by the server (MetaManager with SDE)

Isite Software Status
        - Version 2.06a available for Windows 98/NT and UNIX
        - Faster indexing and search than 2.01
        - Support for aligned search fields with GILS
        - Synonym support in server

Next Isite Release (July 99)
        - Includes Isearch-2 that does not require local documents for search
        - Will support remote hosting of Clearinghouse Nodes fed by crawler from websites
        - Software exports server characteristics (centroids) based on Spatial, Temporal, and Word frequencies to support “smart” referrals

Multi-Tier Clearinghouses

Web client

Gateway

Clearinghouse Nodes

(Z39.50 Servers)

crawler

Web Servers

Your Search Page

Place:

Time: 

Search Terms:

Alaska

after 1988

volcano

Your Search Results

See Also:

Isite Installation
        - Isite is a public domain collection of indexer and server software
        - Iindex is used to build a searchable index
        - Isearch is a local (non-Z39.50) search tool for testing
        - Zserver is the process that serves Z39.50
        - Zclient is a command-line test program

Metadata Prep for Isite

1. Develop FGDC-structured metadata

2. Save as SGML or XML

3. Make Text, SGML, and HTML forms 

OR

Use mp to convert from SGML to HTML 

on-the-fly

Sorting out the Installation

Isite
        -  Iindex
        -  Isearch
        -  zclient
        -  Izclient
        -  Iutil
        -  zserver
        -  zserver.ini
        -  sapi.ini
        -  fgdc.fields
        -  bib1.fgdcmap
        -  gils.fgdcmap
        -  geo.fgdcmap

metadata

index

Place SGML/XML, HTML, and TEXT here

Direct Iindex to place the index files here

Iindex -d  \index\oregon  -t fgdc 

-o fieldtype=fgdc.fields  \metadata\*.sgml

Edit zserver.ini and sapi.ini
        - In zserver.ini:
        - Set or note Port Number
        - Set DBList=oregon
        - In sapi.ini:
        - Make a block for the index “oregon”:

[oregon]

Location=\index

Type=ISEARCH

FieldMaps=\Isitebib1.fgdcmap,

\Isite\gils.fgdcmap,\Isite\geo.fgdcmap

Start and Test zserver
        - Zserver (from command line in window)
        - zclient localhost 6668 oregon “data[1,1035]”

		(search for “data” anywhere in text)
        - Izclient is similar function
        - Should get back records as text
        - All instructions are available on the tutorial at the www.fgdc.gov website

Isite Future
        - Isite software is supported by FGDC and US Patent and Trademark Office
        - Provides a free reference implementation for Z39.50 and the FGDC/GEO Profile
        - Commercial solutions also exist

Commercial Clearinghouse
        - Compusult has a MetaManager Toolkit to build an FGDC-compliant server on top of a RDBMS (Oracle, MS SQL-Server, Access) http://www.fgdctoolkit.com
        - Blue Angel Technologies has a MetaStar Repository for support of many types of metadata (GILS, DC, MARC, GEO, etc.) http://www.blueangeltech.com

Compusult MetaManager
        - Allows FGDC metadata to be stored in many tables (ISO within the year)
        - Preserves hierarchy/collection metadata
        - Manages multiple collections at a site
        - Allows re-usable fields as static value, function, field value(s), or combination
        - Includes web search interface
        - Available for Access ($1995) and Oracle ($5000)

Clearinghouse Search Forms
        - Search access to all registered Clearinghouse Nodes is provided through our several gateways
        - HTML and 2 Java interfaces are available
        - Interest in having “local” search of Clearinghouse Node(s)

Access to Clearinghouse
        - Fill-in HTML forms (Isite gateway)
        - Enhanced HTML forms (BlueAngel/FGDC)
        - Java applet (MEL)

Access has been restricted to gateway 

interfaces and limited HTML capabilities

Community Considerations
        - Clearinghouse entry points should portray the same kinds of interface items to build user familiarity
        - Gateways should reflect the same lists of servers to assure current content
        - Innovation can benefit general user interface development

How it works now

Web

server

Web client

Gateway

Clearinghouse

Nodes

Z39.50

cgi/servlet

list of servers

applet

or form

Formal FGDC gateways...
        - Use Blue Angel gateway software
        - use a servlet to generate HTML form with a session ID embedded in it
        - can now be used to perform search based on forms from remote, non-gateway sites

To host your own forms
        - Need a web server with perl or programming support
        - A startup form -OR- a program that generates a form on-the fly
        - Program to GET the session ID and server list from the Gateway
        - URL of Gateway servlet

How we did it

Web

server

Web client

Gateway

Clearinghouse

Nodes

Z39.50

cgi/servlet

list of servers

applet

or form

Your

Web server

script

HTML

Client fetches form

How we did it

Web

server

Web client

Gateway

Clearinghouse

Nodes

Z39.50

cgi/servlet

list of servers

applet

or form

Your

Web server

script

HTML

ID and server list folded into form

How we did it

Web

server

Web client

Gateway

Clearinghouse

Nodes

Z39.50

cgi/servlet

list of servers

applet

or form

Your

Web server

script

HTML

Form passed to client with all info

How we did it

Web

server

Web client

Gateway

Clearinghouse

Nodes

Z39.50

cgi/servlet

list of servers

applet

or form

Your

Web server

script

HTML

Form POSTed to Gateway host

You can be the designer
        - Only the initial search forms are under your control
        - Form elements may have as much or as little presented as you need
        - Must follow the variable naming convention of the Gateway
        - Does not yet allow for customization of the results interface

Clearinghouse and OpenGIS
        - Clearinghouse has been a useful exercise in helping people get to GIS data
        - An increasing proportion of our clientele are not GIS-literate and need map interfaces
        - Support of Clearinghouse principles also needs industrial support to expand the advertising and publication of spatial data

Catalog Services
        - OpenGIS Consortium put out an RFP last year for solutions on spatial data and services discovery (Catalog Services)
        - Two respondent teams including FGDC, NASA, ESRI, Intergraph, and Oracle responded
        - We are working on a single solution to be released as an OGC standard in July

Catalog Services
        - Proposal is to support three protocols with interoperability specified between them:
        - CORBA
        - COM/OLEDB
        - XML on HTTP
        - XML on HTTP is modeled after and is compatible with Z39.50 functions
        - Support by GIS vendors will be helpful

Web Mapping Testbed
        - To provide a testing ground for interoperable map request techniques, the OGC is hosting a web mapping testbed this year
        - Sponsors are FGDC, NASA, NIMA and Army TEC
        - 15 vendor consortia are participating

Web Mapping Approach

Data

Map 

Servers

Viewer

Clients

Web Mapping Testbed
        - A physical Lab is being configured in Gaithersburg MD
        - A virtual lab is being hosted on the Internet
        - If you have map server software, data, and metadata and are interested in hosting WMT software for a few months you can participate, too