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What is OPeNDAP?

OPeNDAP is a software framework that simplifies all aspects of scientific data networking, allowing simple access to remote data. Local data can be made accessible to remote locations regardless of local storage format by using OPeNDAP servers. Existing, familiar data analysis and visualization applications can be transformed into OPeNDAP clients (i.e., applications able to access remote OPeNDAP served data).

Take a look at our answer to the question "What Will OPeNDAP Do For Me?".

OPeNDAP is a protocol for requesting and transporting data across the web. The current OPeNDAP Data Access Protocol (DAP) uses HTTP to frame the requests and responses. For details on the OPeNDAP DAP, see our " OPeNDAP Data Access Protocol--DAP 2.0 -- DRAFT" document.

OPeNDAP is a community of users working together to use, improve, and extend the OPeNDAP protocol and software.

Design Principles

The design of the OPeNDAP software was based on these two consideration:

  • data are often most appropriately distributed by the individual or group that has developed them; and
  • the user will in general like to access data from the application software with which s/he is most familiar.

This has resulted in a highly distributed system that allows users to control the distribution of their own data and the way they access data from remote sites.

Community Driven Project

OPeNDAP is a community driven project for developing an end-to-end system for locating, understanding, accessing, and using scientific data. The OPeNDAP project has already developed:

  • the OPeNDAP data model
  • the OPeNDAP transport protocol
  • the OPeNDAP software framework
    • C++ and Java implementations of the data model and transport protocol
    • a set of OPeNDAP servers
    • a set of OPeNDAP clients

Not Just Oceanography

Although OPeNDAP was originally designed and developed by oceanographers and computer scientists for oceanographic data, there is nothing in the design of OPeNDAP that constrains its use to oceanography. Indeed, it has been adopted by the High Altitude Observatory community and is being considered by segments of the meteorological and space science communities.

User Application --> OPeNDAP Client

Once a users data analysis application (or API) is made network-savvy with the OPeNDAP tools, the scope of an application's search for data is extended, i.e., remote data becomes as accessible as local data. A OPeNDAP-enabled application can:

  • Get any data anywhere on the Internet that is served by a OPeNDAP server.
  • Use data from any OPeNDAP server, pretty much regardless of its native format.
  • Still perform all its original functions for accessing data locally.

The truly remarkable part: you don't have to rewrite the code to enable an application to work as a OPeNDAP client.