Overview
ISO/TR 16401-2:2018 defines an abstract test suite (ATS) for evaluating conformity of electronic fee collection (EFC) equipment to the context-data requirements in ISO 17575-2. The document contains executable test cases written in TTCN‑3 (Testing and Test Control Notation version 3) and mirrors the test purposes described in ISO/TR 16401-1. It focuses on conformance testing of the Front End (FE) - including the Front End Communications API and Front End application - and the Back End (BE) in autonomous EFC (GNSS/CN) environments.
Key topics and technical content
- Test cases in TTCN‑3: All test cases are provided as TTCN‑3 modules so testers can execute standardized, repeatable tests.
- Abstract Test Method (ATM): Describes the test architecture where the tester runs TTCN‑3 tests using an emulated communication sub-layer to exercise the IUT (Implementation Under Test) - either FE or BE.
- ATS data structures: Uses ASN.1 data definitions from base standards; complex parameterized structures are redefined in TTCN‑3 where needed.
- PIXIT (Protocol Implementation Extra Information for Testing): Suppliers provide PIXIT information (proforma in Annex B) to support testing and reduce ambiguity.
- Message filtering and default behaviours: Guidance on handling callback events and default ignore behaviours to ensure consistent test executions.
- Naming conventions: Standardized TTCN‑3 naming rules for modules, messages, variables, timers and test-case identifiers to improve readability and interoperability of test suites.
- Conformance testing terminology: Aligns with ISO/IEC testing terms (IUT, SUT, TC, TP, ATS, ATM) for clarity and consistency.
Practical applications
- Test laboratories and certification bodies use ISO/TR 16401-2 to perform conformance testing and type approval of EFC on-board equipment (OBE) and backend systems.
- Equipment manufacturers and ITS integrators use the ATS to validate Front End Communications API and Front End application behaviour against ISO 17575-2 requirements.
- Toll service providers and system operators rely on these tests to ensure interoperability across GNSS/CN autonomous tolling deployments and to achieve comparable results across testing sites.
Who should use this standard
- EFC equipment manufacturers (OBE vendors)
- Conformance test laboratories and certification authorities
- Toll operators and service providers
- ITS (Intelligent Transport Systems) test engineers and system integrators
- Software developers implementing Front End Communications APIs
Related standards
- ISO/TR 16401-1 - Test purposes for EFC conformity evaluation
- ISO 17575-2 - Application interface definition: context data (requirements under test)
- ISO 17575-1 - Charging (related application interface definitions)
Keywords: ISO/TR 16401-2, electronic fee collection, EFC, abstract test suite, TTCN‑3, ISO 17575-2, conformance testing, Front End Communications API, PIXIT, GNSS/CN.
Open preview (PDF)Electronic fee collection — Evaluation of equipment for conformity to ISO 17575-2 — Part 2: Abstract test suite
