ADL software provides a distributed searching mechanism
for geospatially referenced data collections. Distributed means you can
search different types of databases at different locations. ADL software
has the ability to use existing metadata. ADL defines a general architecture
that makes it possible to use with a wide variety of databases, often
without changing the content or information within the database.
The ADL architecture is centered around a middleware server that provides
multiple clients with a uniform view of multiple heterogeneous collection
servers. The ADL search buckets are the principal mechanism by which this
uniform view is achieved:
- Clients formulate queries in terms of collection-neutral
- The middleware server translates and forwards queries to the collection
- Collections servers are responsible for evaluating the queries in
ways that are meaningful for their respective collections.