Ingrid uses OPeNDAP to exchange data with itsself, get data from other OPeNDAP servers, and send data to OPeNDAP clients. While the implementation does not depend on the OPeNDAP core, there have been no intended extensions to the OPeNDAP protocol: all the uniquely Ingrid information is encoded in the filename part of the URL, which by definition is site dependent.