With the increasing prevalence of NFC-enabled smartphones, contactless communication is gaining more and more influence in everyday life. The simple “tap and go” for example to exchange contact details is a fast and likable experience. However, paying with NFC-enabled smartphones instead of credit cards requires a high degree of trust in this very convenient but rather new payment method. This trust is created by tested and proven technology working reliably and smoothly. The NFC Forum addresses this question of trust by offering device certification for global interoperability, which is based on a set of authorized test labs using approved test tools. Every approved test tool implements appropriate test specifications proving that a certified NFC-enabled device has implemented all device requirements and is compliant to the specifications.

NFC Forum distinguishes between different versions of the device requirements specification and the corresponding set of test cases published in the so-called Test Case Category List. These documents are regularly being updated since specifications are constantly improved by the members of the NFC Forum. In order to set a stable frame for certification testing, so-called Certification Releases have been published by NFC Forum with overlapping validity periods, so that an ongoing device certification can be finalized according to the scope of requirements and test cases it started with.

 

What are Approved Test Tools and How Can the NFC Forum Ensure that they Provide the Latest Specifications?

An approved test tool as defined by the NFC Forum has undergone a validation conducted by an independent third-party laboratory. The approval process for test tools is constantly anticipating the cycle of upcoming certification releases. A certification release is a set of specific versions of tests to be implemented and of forms to be submitted and it replaces the former term “waves”. NFC Forum has authorized only two labs for the validation of test tools, one for Digital Protocol, focusing on protocol testing, and one for RF Analog, focusing on the physical interface. Although the validation requirements are identical for both, the further test tool requirements have been defined for RF Analog. Both are going to be explained in the next paragraphs.

 

Validation Requirements for RF Analog

Validation testing is split into three main categories of testing: mode 1, mode 2 and mode 3.

Mode 1 testing starts with pre-mode 1 phase in order to check whether the test tool measures DC voltages and frequencies correctly compared to third party reference devices (digital volt meter, frequency counter). Running each and every test case and analyzing the calculation of the corresponding verdict of the tool are the focus of mode 1 testing. This includes variants to check whether the tool correctly reports a failure, when test criteria have not been met.

Mode 2 is an “Inter Lab Comparison Test” (ILCT) in which a specific sample provided by NFC Forum is used for a subset of test cases at all 14 positions defined by the core specifications in order to ensure consistency between all the authorized test labs. In addition, the “Amplifier Characterization Tests” (ACT) are executed to prove repeatability and consistency of RF measurements by all approved test tools enforcing the correct behavior of a necessary hardware component, an amplification stage.

Mode 3 checks the sensitivity of the test tool by testing against another (verified) test tool. The setup requires the one test tool to transmit and the other to receive and the other way round. This way, the correct measurement of externally generated signals is verified as well as the correct generation of signals by the tool itself.

Furthermore, the “Reference Equipment Verification Test” (REVT) is performed on the NFC Forum Reference Antennas as part of the test tool hardware. Every supplier of NFC Forum Approved Test tools has to perform this verification test for each Reference Antenna shipped to customers.

Both validation houses have to evaluate the general tool requirements for completeness of the test cases, correct interpretation of results for generating verdicts, usability and update features, documentation of the user interface as well as the integrity and security of the test case results.

 

Validation Requirements for the Digital Protocol

Digital Protocol requires testing against two reference samples provided by the NFC Forum. Both samples must successfully pass the same 80% of all applicable test cases. The validation for Digital Protocol testing includes the Tag 1 to Tag 4 operation test cases which are dedicated to the reader/writer mode.
 

Validation Requirements for LLCP and SNEP

Regarding the validation for LLCP (Logical Link Layer Control Protocol) and SNEP (Simple NDEF Exchange Protocol), the so called Peer-to-Peer Mode is addressed, where both sides can be active and passive.

Only a part of the respective test cases have reached a stable state (26 of 67 test cases for LLCP and 24 of 25 test cases for SNEP). So-called phase 1 comprises these stable test cases. All
other test cases have to be validated in phase 2. For this phase, a firm schedule still needs to be
set by NFC Forum and the validation laboratory. As a consequence, all current approvals for LLCP/
SNEP have been given for phase 1 tests, none for phase 2.

 

UT³ Platform Validation Status

 

 

 

Download Testability Times 2014

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• NFC Forum
• NFC
• LLCP
• SNEP
• Analog
• Digital