What is the GEO DAB
GEO DAB is a key component of the GEOSS Common Infrastructure (GCI), transparently connecting GEOSS User’s requests to the resources shared by the GEOSS Providers.
GEO DAB scope is to simplify cross and multi-disciplinary discovery, access, and use (or reuse) of disparate data and information.
GEO DAB is a brokering framework that interconnects hundreds of heterogeneous and autonomous supply systems (the enterprise systems constituting the GEO metasystem) by providing mediation, harmonization, transformation, and QoS capabilities.
How it works
The GEO DAB applies the broker pattern, which separates users of services (clients) from providers of services (servers) by inserting an intermediary, called a broker. When a client needs a service, it queries a broker via a service interface. The broker then forwards the client's service request to a server, which processes the request. The GEO DAB presently provides broker components for discovery, access, semantics-enabled search.
Step by Step
The GEO DAB intercats with external systems by means of softare modules called Profilers and Accessors.
The following high-level steps are executed upon uers' requests.
Supported Standards

Profilers
Each profiler is in charge of publishing a service interface which client applications can connect to (e.g. an OGC CSW interface, an OpenSearch interface, etc). Each incoming request is translated by the profiler into the GEO DAB internal query language. After GEO DAB has executed the request, profilers translate the result according to what is required by the client application.The GEO DAB presently provides profilers for the following service interfaces.

OGC CSW 2.0.2 AP ISO 1.0

OGC CSW 2.0.2 ebRIM EO

OGC CSW 2.0.2 ebRIM CIM

ESRI GEOPORTAL 10

OAI-PMH 2.0

OpenSearch 1.1

OpenSearch 1.1 ESIP

OpenSearch GENESI DR

CKAN

CUAHSI HIS-Central

ESRI REST API 10.3

Accessors
Each accessor is in charge of connecting to external servers publishing a specific service interface (e.g. OAI-PMH, OGC WCS, etc). Accessors translate requests expressed according to the GEO DAB internal query language into requests expressed according to the external system one. Besides, they execute data and metadata model mapping from the external ones to the GEO DAB internal ones. The GEO DAB presently provides accessors for the following service interfaces.

OGC WCS 1.0.0, 1.1.2, 2.0.1

OGC WMS 1.1.1, 1.3.0

OGC WFS 1.0.0, 1.1.0, 2.0.0

OGC WMTS 1.0.0

OGC SOS 1.0.0, 2.0.0, 2.0.0 Hydro Profile

OGC WPS 1.0.0

OGC CSW 2.0.0 Core

OGC CSW 2.0.2 AP ISO 1.0

OGC CSW 2.0.2 ebRIM/EO AP

OGC CSW 2.0.2 ebRIM/CIM AP

IRIS Station

HYRAX THREDDS SERVER 1.9

OAI-PMH 2.0

GBIF

DIF

HYDRO

UNAVCO

CDI 1.04, 1.3, 1.4

ISO19115-2

THREDDS 1.0.1, 1.0.2

THREDDS-NCISO 1.0.1, 1.0.2

THREDDS-NCISO-PLUS 1.0.1, 1.0.2

INPE

CKAN

DCAT

GI-cat

ESRI GEOPORTAL 10

NCML-OD

BCODMO

NCML-CF

NetCDF-CF 1.4

FTP populated with supported metadata types

WAF Web Accessible Folders

GeoNetwork (2.2.0 or greater)

Ecological Markup Language 2.1.1

NERRS (National Estuarine Research Reserve System)

HMA CSW 2.0.2 ebRIM/CIM

HDF

IADC DB (MySQL)

GrADS-DS