Standardisation and Interoperability

Technical standards for EPS technology cover data exchange as well as equipment and communications. Standards aim to ensure consistency in the way that data is stored, accessed and transferred between a MOP and a reader, and between transport operators and payment service providers. Although standards are necessary, they are not always sufficient since a standard may have many options that may be selected and so some additional specifications sometimes known as ‘profiles’, may be needed.

Standards have been developed for tags used for tolling, such as Title 21 (generally California only), ISO-18000-6C and European Norm EN15509: 2007 (European Union) To confirm technical compliance, a MOP and the readers would commonly be subject to conformance test procedures, also defined by standards.

The world’s largest, multiple agency ETC scheme is E-ZPass that depends on a common proprietary single-source RFID tag (used as a MOP) supported by procedural and business level agreements amongst all participating operators known as the InterAgency Group, IAG. (See E-ZPass Group: Operating Agreement and Reciprocity Agreement (http://www.e-zpassiag.com).

For public transport, the most common standards are for smart cards – EMV (Europay, MasterCard and Visa) and MIFARE (a proprietary technology) for hybrid (contact/wireless) and wireless cards respectively. The Near Field Communication (NFC) standards embedded in cards and mobile phones are also used for MOPs, most commonly for public transport.

Certification processes can help ensure that equipment is safe and fit for purpose; open procurement processes are a means of stimulating competition.

With some exceptions, the challenges to establish interoperability involve reaching agreement at both the technical and contractual levels. Agreements are often use to describe operational procedures between organisations and, if this process is incomplete, it is possible that the benefits of interoperability may not be fully delivered, either to the transport service provider, to users or to both. For example, a group of transport service providers who wish to employ a smart card that complies with International Standards Organisation (ISO) / International Electrotechnic Commission (IEC) 14443 as a MOP that is to be issued and accepted by each provider will need to agree on:

• the content of the data stored
• how transaction data should be shared
• the commercial terms for processing and paying for payment transactions generated

Interoperability enables a single MOP to be accepted within and across modes. Adopting this policy can reduce procurement risk of MOPs by transport service providers sharing a common specification and can increase user choice amongst multiple competing MOP providers. If a single provider’s electronic tolling tag is usable at multiple locations then this would be de facto interoperability, but procurement risk depends on the delivery performance of one provider and there may be limited consumer choice of MOP variants.

An example of a comprehensive, multiple-service provider interoperability model is the European Electronic Toll Service (EETS) that separates the functions of toll collection, tolling account management and process governance, enabling organisations to specialise. In particular, Ireland has one of the most mature EETS schemes in Europe. (See: National Roads Authority (Ireland): http://www.nra.ie/tolling-information/)

In general, institutional barriers may slow down or prevent agreement on interoperability and therefore the most successful schemes are those that have addressed these. Efforts to ensure interoperability for Electronic Toll Collection (ETC) have not included procedures and evidential requirements for cross-border enforcement (for example the EETS definition does not include this).

Other challenges exist in establishing new services with incompatible competing standards such as physical interfaces for Electric Vehicle charging and transaction reports generated by GNSS OBUs to report road usage.

Overall, despite the many benefits to users of interoperability described here, the benefits to an operator may be limited, or there may be a net cost to the operators that could make it difficult to implement interoperability or prevent it happening at all.