— rules and guidelines for defining extensible biometric data interchange formats that are extensible without invalidating previous data structures;

— the meaning of common data elements for use in extensible biometric data interchange formats;

— common data structures for tagged binary data formats based on an extensible specification in ASN.1;

— common data structures for textual data formats based on an XML schema definition; and

— conformance testing concepts and methodologies for testing the syntactic conformance of biometric data blocks.