Data Filtering for Cross Domain Solutions

New Approaches to Data Filtering for Cross Domain Solutions

To improve robustness and cost-effectiveness of Cross Domain Solutions (CDS), modern filtering designs are incorporating:

DFDL - Data Format Description Language

Replace software for data parsing with a declarative approach that uses a DFDL schema that describes the data format, along with the Daffodil open source DFDL processor to parse data, revealing it as XML (or JSON) for inspection, validation, and sanitization. Daffodil is used for subsequent 'unparse' back to the native format.

XML Validation and Transformation

Use an XML-centric approach to data inspection, validation, and sanitization.
Use XML Schema and Schematron for data validation.
Use XSLT or XQuery-based transformations on XML data.

Filter Componentization

Augment proprietary product filter sets with filters built to standard APIs from the Filter Componentization Effort (FCE) 1.0.

Tresys provides services to help the CDS community with incorporation of these technologies including:

  • DFDL Schema authoring services
    • For industry/military standard data formats
    • For your project specific data formats
  • Consulting on DFDL schema designs that you develop in-house
  • Hands-on training on DFDL, and on use of XML technologies for filtering
  • Filter development and test services
  • Daffodil open source software enhancement and support services

CDS systems must be highly robust, yet must also incorporate innovations to further the state-of-the-art. Large open source software libraries like Daffodil enable innovative approaches, but introduce a large body of new software into the CDS. Open source means your engineers could self-support, but the reality of a large and unfamiliar code base adds risks that are particularly troubling in CDS applications.

Tresys engineers have been the core contributors to Daffodil, taking it from its genesis to its status today as Apache Daffodil (Incubating). See for more information.

Apache, Apache Daffodil, and Daffodil are trademarks of The Apache Software Foundation.

Tresys DFDL Data Format Description Language & Daffodil Open Source - Public Overview from Mike Beckerle