XAdES/CAdES Remote Plugtests event

The objective of this XAdES/CAdES remote Plugtests event was to improve interoperability of Advanced Electronic Signatures for XML and CMS documents, also known as XAdES and CAdES.

ETSI Plugtests™ organised this remote XAdES/CAdES interoperability test event in October/November 2010. Participants joined the event by connecting to the ETSI Plugtests Electronic Signature Portal as and when required.

It aimed at conducting more extensive interoperability testcases on XAdES 1.3.2 and CAdES 1.7.4, as well as on the new versions of signatures, XAdES 1.4.1 and CAdES 1.8.1.

The tests used in this event were an extension of the test coverage of the specifications for XAdES v1.3.2 and CAdES v1.7.4 with respect to previous Plugtests events, including signatures evolution, in order to simulate real life situations. A new set of specific testcases was also provided to cover the extensions defined in the new XAdES v1.4.1 and CAdES v1.8.1.

The test coverage has been extended compared to previous events, with completely new testcases, including testing signatures evolution, simulating real life situations to:

  • assess the level of interoperability of XAdES and CAdES;
  • consolidate solutions to interoperability issues which have been identified in previous events; 
  • identify additional issues which should be taken into account in future XAdES/CAdES standardization activities;
  • improve the quality of XAdES/CAdES specifications; and
  • ease the introduction of XAdES/CAdES signatures, by providing the means to solve interoperability problems before widespread deployment.

The most interesting issue raised with respect to the CAdES signature testing was the different interpretations of the latest version of the TS 101 733 (v 1.8.1), especially the ArchiveTimeStamp unsigned attribute dealt in clause 6.4.1 and annex K. It appears that readers of these two parts of the specification reach different conclusions which could result in a lack of interoperability. A request for clarification of theses clauses in the specification, has been raised to the TC ESI.

Another major outcome is that ETSI had noted, while preparing the event, a discrepancy in the tag of an XML element (xadesv141:XAdESTimeStamp) between the Technical Specification document and one of the XML Schema files that define the XML Schema of XAdES v.1.4.1(xadesv141:XAdESTimeStampV2). This has been discussed with participants during the event and we agreed on one solution as being the one that would have the least impact on their implementations. As a result, a new version of XAdES version 1.4.2, with this decision implemented, was issued.