This part of ISO/TS 14907 describes tests that verify on-board unit (OBU) conformance of implementations of functions and data structures@ as defined in the implementation conformance statement based on ISO 14906:2011/Amd1:2015@ for electronic fee collection (EFC) applications. After the tests of isolated data items and functions (C.2 to C.4)@ an example is given for testing of a complete EFC transaction (C.3). The scope of this part of ISO/TS 14907 comprises definitions of OBU conformance assessment tests of ?? basic dedicated short-range communication (DSRC) L7 functionality@ ?? EFC application functions@ ?? EFC attributes (i.e. EFC application information)@ ?? the addressing procedures of EFC attributes and (hardware) components [e.g. integrated circuit cards (ICC) and man-machine interfaces (MMI)]@ ?? the EFC transaction model@ which defines the common elements and steps of any EFC transaction@ and ?? the behaviour of the interface so as to support interoperability on an EFC-DSRC application interface level@ see Figure 1. The purpose of this part of ISO/TS 14907 is to define tests that ?? assess OBU capabilities@ ?? assess OBU behaviour@ ?? serve as a guide for OBU conformance evaluation and type approval@ ?? achieve comparability between the results of the corresponding tests applied in different places at different times@ and ?? facilitate communications between parties. Whereas@ this part of ISO/TS 14907 defines examples of test cases for DSRC and EFC functionality in Annex C@ it does not intend to specify a complete test suite for a certain implementation. To compose a test suite for a specific EFC implementation@ the test cases may have to be modified and new test cases may have to be defined and added in order for the conformance test to be complete. It can be useful to take into account the following considerations when defining a complete test suite ?? small range: ??exhaustive testing?? of critical interoperability/compatibility features@ ?? large range: testing of boundaries and random values@ and ?? composite types: testing of individual items in sequence or parallel. Figure 2 shows the overall procedure of conformance testing. Figure 3 gives a more detailed picture of the interface between the entity performing the conformance test and the supplier of the Device Under Test (DUT). By the EFC application specification@ the implementation conformance statement proforma and the implementation extra information for testing proforma the supplier is requested to provide the DUT (OBU)@ containing the Implementation Under Test (IUT)@ as well as the documentation needed to perform the tests. More details on the content of the different documents are given in Clause 5 on OBU and supporting information. NOTE 1 The Device Under Test contains the Implementation Under Test. It is outside the scope of this part of ISO/TS 14907 to define tests that assess ?? performance@ ?? robustness@ and ?? reliability of an implementation. NOTE 2 ISO/TS 14907-1 defines test procedures that are aimed at assessing performance@ robustness and reliability of EFC equipment and systems. NOTE 3 The ISO/IEC 10373 series defines test methods for proximity@ vicinity@ integrated circuit(s) cards and related devices that may be relevant for OBUs that support such cards. Annex D provides an informative overview of Japanese OBE conformance tests that are based on the ISO/TS 14907 series@ in order to illustrate how these can be applied in practice.