Changes between Initial Version and Version 1 of RemoteSearch

Timestamp:

12/21/09 10:00:22 (15 years ago)

Author:

awarnock

Comment:

--

RemoteSearch

@@ +1 @@
+= Remote & Distributed Search =
+
+|| '''Date''' || 2009/12/20 ||
+|| '''Contact(s)''' || A. Warnock (A/WWW Enterprises), D. Nebert (USGS/FGDC), L. Miao (GMU), Z. Li (GMU), H. Wu (GMU)  ||
+|| '''Last edited''' || [[Timestamp]] ||
+|| '''Status''' || Proposed for voting ||
+|| '''Assigned to release''' || 2.5 ||
+|| '''Resources''' || No additional resources needed ||
+
+== Overview ==
+Some collections may be too large or too dynamic to harvest directly while still being desirable to
+search within the context of the general search capability.  This proposal will add the ability to 
+refer some search requests to remote collections and return results along with results from local collections.
+
+=== Proposal Type ===
+ * '''Type''': Core Change
+ * '''App''': !GeoNetwork
+ * '''Module''': Search Interface
+
+=== Links ===
+ * '''Documents''':
+ * '''Email discussions''': See thread on ''Proposal: Local harvesting and remote search'' on geonetwork-devel list
+ * '''Other wiki discussions''':
+
+=== Voting History ===
+ * Vote proposed by A. Warnock on 2009-12-20.
+
+----
+
+== Motivations ==
+The current configuration implements search only on locally-held collections.  In order to provide
+full functionality as either a geospatial portal or clearinghouse, it would be desirable for !GeoNetwork
+to have the ability to search remote collections (at least via CSW or Z39.50) without harvesting them
+locally.
+
+== Proposal == 
+A number of metadata sources in GEOSS are either too large
+(250,000 - 1 million records or more) or too dynamic (several
+updates/hour, perhaps related to emergency conditions) to harvest and
+hold locally.  In these cases, we anticipate that searching through the
+clearinghouse instance should be performed as a distributed search
+against the original collection, rather than against a locally-held
+harvested collection, and further, that this process should be
+transparent to the end-user.  That is, while such collections may be
+presented to the end user as an optional source to be searched, they
+should not be expected to know which collections are held in the
+clearinghouse and which are searched remotely, nor should the end user
+be directed away from the clearinghouse site to search these remote
+sites separately.
+
+We are fully cognizant of the network latencies involved in such a
+scenario, having had direct experience with it in the FGDC Clearinghouse
+network in years past.  Nonetheless, support for distributed, remote
+searching is seen to be unavoidable within the GEOSS framework.  The
+basic client functions for doing distributed, remote search is already
+in GeoNetwork - we propose to implement it as part of the search
+interface, at least through the CSW API.  Note that, in GEOSS anyway,
+clearinghouse and portal functions are separate - portals provide the
+user interface, clearinghouses provide the programmatic search interface
+to the portals via CSW.
+
+=== Backwards Compatibility Issues ===
+None anticipated.
+
+== Risks ==
+None forseen.  Development will take place on a separate branch so that testing can take place before merging into the trunk.
+
+== Participants ==
+ * A. Warnock (A/WWW Enterprises)
+ * D. Nebert (USGS/FGDC)
+ * L. Miao (GMU)
+ * Z. Li (GMU)
+ * H. Wu (GMU)