It is suitable for installation in the cable headend, uplinks and development labs to test application conformance and validity prior to transmission. S&T's TSBroadcaster 2 supports ETV and OCAP validation through a SOAP interface connection to the XAV Server.

XAV applies objective and repeatable tests to the application resource files which compose the application. Test categories are:

• Validity. All resources are checked for adherence to mandatory constraints and that they are well formed. Tests if the application as a whole adheres to mandatory content and behavioral constraints.

• Interoperability. Determines whether the application accesses non-standard APIs in platform-defined packages. Tests if the application defines all referenced APIs in application-defined packages. Establishes whether the content or behavior uses non-interoperable features.

• Security. Checks for references to privileged operations for which it has failed to request permission. Tests if the application relies upon always being granted access to a privileged operation that may be denied at runtime. Determines if the application attempts to exploit potential implementation defects to avoid security controls.

  If the application is signed, then XAV tests that the application contains valid forms of all necessary security files (digests, signatures, certificates, permission request files).

• Efficiency. Establishes if a resource or part of a resource is going to be ignored upon execution. Eliminating these issues can make the application more efficient to transmit and execute. For example, a text chunk in a PNG image will be ignored under OCAP 1.0 so that chunk could be safely removed from the file.

XAV can also be integrated with an authoring tool by programmatically accessing XAV services in order to provide compliance and performance testing during the application development and authoring process.

For GEM application development, XAV's Platform Reference reporting assists by analyzing and reporting on Java platform usage in varying levels of detail.