|1. Introduction||3. Interoperability layers|
The interoperability principles are fundamental behavioural aspects to drive interoperability actions. This chapter sets out general interoperability principles which are relevant to the process of establishing interoperable European public services. They describe the context in which European public services are designed and implemented.
The twelve underlying principles  of the EIF are grouped into four categories:
- Principle setting the context for EU actions on interoperability (No 1);
- Core interoperability principles (Nos 2 to 5);
- Principles related to generic user needs and expectations (Nos 6 to 9);
- Foundation principles for cooperation among public administrations (Nos 10 to 12).
2.2 Underlying principle 1: subsidiarity and proportionality
The subsidiarity principle requires EU decisions to be taken as closely as possible to the citizen. In other words, the EU does not take action unless this is more effective than the same action taken at national level. The proportionality principle limits EU actions to what is necessary to achieve the objectives of the Treaties.
Concerning interoperability, a European framework is justified to overcome differences in policies that result in heterogeneity and lack of interoperability and that put at risk the digital single market.
The EIF is envisaged as the ‘common denominator’ of interoperability policies in Member States. Member States should enjoy sufficient freedom to develop their NIFs with respect to EIF recommendations. NIFs are expected to be tailored and extended in such a way that national specificities are properly addressed.
Recommendation 1: Ensure that national interoperability frameworks and interoperability strategies are aligned with the EIF and, if needed, tailor and extend them to address the national context and needs.
2.3 Underlying principle 2: openness
In the context of interoperable public services, the concept of openness mainly relates to data, specifications and software.
Open government data (here simply referred ‘open data’) refers to the idea that all public data should be freely available for use and reuse by others, unless restrictions apply e.g. for protection of personal data, confidentiality, or intellectual property rights. Public administrations collect and generate huge amounts of data. The Directive on the reuse of public sector information (PSI)  encourages Member States to make public information available for access and reuse as open data. The INSPIRE Directive  requires, in addition, sharing of spatial datasets and services between public authorities with no restrictions or practical obstacles to its reuse. This data should be published with as few restrictions as possible and clear licences for its use to allow better scrutiny of administrations’ decision-making processes and realise transparency in practice.
Recommendation 2: Publish the data you own as open data unless certain restrictions apply.
Open data is discussed in more detail in section 4.3.4.
Recommendation 3: Ensure a level playing field for open source software and demonstrate active and fair consideration of using open source software, taking into account the total cost of ownership of the solution.
The use of open source software technologies and products can help save development cost, avoid a lock-in effect and allow fast adaptation to specific business needs because the developer communities that support them are constantly adapting them. Public administrations should not only use open source software but whenever possible contribute to the pertinent developer communities. Open source is an enabler of the underlying EIF principle on reusability.
The level of openness of a specification/standard is decisive for the reuse of software components implementing that specification. This also applies when such components are used to introduce new European public services. If the openness principle applies in full:
- all stakeholders have the opportunity to contribute to the development of the specification and a public review is part of the decision-making process;
- the specification is available for everyone to study;
- intellectual property rights to the specification are licensed on FRAND  terms, in a way that allows implementation in both proprietary and open source software , and preferably on a royalty-free basis.
Due to their positive effect on interoperability, the use of open specifications has been promoted in many policy statements and is encouraged for European public service delivery. The positive effect of open specifications is demonstrated by the internet ecosystem. However, public administrations may decide to use less open specifications if open ones do not exist or do not meet functional needs. In all cases, specifications should be mature and sufficiently supported by the market, unless they are being used to create innovative solutions.
Recommendation 4: Give preference to open specifications, taking due account of the coverage of functional needs, maturity and market support and innovation.
Lastly, openness also means empowering citizens and businesses to get involved in the design of new services, to contribute to service improvement and to give feedback about the quality of the existing public services.
2.4 Underlying principle 3: transparency
Transparency in the EIF context refers to:
- Enabling visibility inside the administrative environment of a public administration. This is about allowing other public administrations, citizens and businesses to view and understand administrative rules, processes , data, services and decision-making.
- Ensuring availability of interfaces with internal information systems. Public administrations operate a large number of what are often heterogeneous and disparate information systems in support of their internal processes. Interoperability depends on ensuring the availability of interfaces to these systems and the data they handle. In turn, interoperability facilitates reuse of systems and data, and enables these to be integrated into larger systems.
- Securing the right to the protection of personal data, by respecting the applicable legal framework for the large volumes of personal data of citizens, held and managed by Public Administrations.
Recommendation 5: Ensure internal visibility and provide external interfaces for European public services.
2.5 Underlying principle 4: reusability
Reuse means that public administrations confronted with a specific problem seek to benefit from the work of others by looking at what is available, assessing its usefulness or relevance to the problem at hand, and where appropriate, adopting solutions that have proven their value elsewhere. This requires the public administration to be open to sharing its interoperability solutions, concepts, frameworks, specifications, tools and components with others.
Reusability of IT solutions (e.g. software components, Application Programming Interfaces, standards), information and data, is an enabler of interoperability and improves quality because it extends operational use, as well as saving money and time. This makes it a major contributor to the development of a digital single market in the EU. Some EU standards and specifications also exist in the DIFs and should be applied more widely. For example, the INSPIRE Directive sets out interoperability standards for addresses, cadastres, roads and many other data topics of relevance to many public administrations. These existing standards and specifications can and should be used more widely beyond the domain for which they were originally developed.
Several public administrations and governments across the EU already promote sharing and reuse of IT solutions by adopting new business models, promoting the use of open source software for key ICT services and when deploying digital service infrastructure.There are some key challenges that limit the sharing and reuse of IT solutions, at technical, organisational, legal and communication levels.
The ISA² sharing and reuse framework for IT solutions  provides recommendations for public administrations to help them overcome these challenges and share/ reuse common IT solutions. Reuse and sharing can be effectively supported by collaborative platforms.
Recommendation 6: Reuse and share solutions, and cooperate in the development of joint solutions when implementing European public services.
Recommendation 7: Reuse and share information and data when implementing European public services, unless certain privacy or confidentiality restrictions apply.
2.6 Underlying principle 5: technological neutrality and data portability
When establishing European public services, public administrations should focus on functional needs and defer decisions on technology as long as possible in order to minimise technological dependencies, to avoid imposing specific technical implementations or products on their constituents and to be able to adapt to the rapidly evolving technological environment.
Public administrations should provide for access and reuse of their public services and data irrespective of specific technologies or products.
Recommendation 8: Do not impose any technological solutions on citizens, businesses and other administrations that are technology-specific or disproportionate to their real needs.
The functioning of the digital single market requires data to be easily transferable among different systems to avoid lock-in, support the free movement of data. This requirement relates to data portability - the ability to move and reuse data easily among different applications and systems, which becomes even more challenging in cross-border scenarios.
Recommendation 9: Ensure data portability, namely that data is easily transferable between systems and applications supporting the implementation and evolution of European public services without unjustified restrictions, if legally possible.
2.7 Underlying principle 6: user-centricity
Users of European public services are meant to be any public administration, citizen or businesses accessing and benefiting from the use of these services. Users’ needs should be considered when determining which public services should be provided and how they should be delivered.
Therefore, as far as possible, user needs and requirements should guide the design and development of public services, in accordance with the following expectations:
- A multi-channel service delivery approach, meaning the availability of alternative channels, physical and digital, to access a service, is an important part of public service design, as users may prefer different channels depending on the circumstances and their needs;
- A single point of contact should be made available to users, to hide internal administrative complexity and facilitate access to public services, e.g. when multiple bodies have to work together to provide a public service;
- Users’ feedback should be systematically collected, assessed and used to design new public services and to further improve existing ones;
- As far as possible, under the legislation in force, users should be able to provide data once only, and administrations should be able to retrieve and share this data to serve the user, in accordance with data protection rules;
- Users should be asked to provide only the information that is absolutely necessary to obtain a given public service.
Recommendation 10: Use multiple channels to provide the European public service, to ensure that users can select the channel that best suits their needs.
Recommendation 11: Provide a single point of contact in order to hide internal administrative complexity and facilitate users’ access to European public services.
Recommendation 13: As far as possible under the legislation in force, ask users of European public services once-only and relevant-only information.
Recommendation 12: Users should be asked to provide only the information that is absolutely necessary to obtain a given public service.
2.8 Underlying principle 7: inclusion and accessibility
Inclusion is about enabling everyone to take full advantage of the opportunities offered by new technologies to access and make use of European public services, overcoming social and economic divides and exclusion.
Accessibility ensures that people with disabilities, the elderly and other disadvantaged groups can use public services at service levels comparable to those provided to other citizens.
Inclusion and accessibility must be part of the whole development lifecycle of a European public service in terms of design, information content and delivery. It should comply with e-accessibility specifications widely recognised at European or international level .
Inclusion and accessibility usually involve multi-channel delivery. Traditional paper-based or face-to-face service delivery may need to co-exist with electronic delivery.
Inclusion and accessibility can also be improved by an information system’s ability to allow third parties to act on behalf of citizens who are unable, either permanently or temporarily, to make direct use of public services.
Recommendation 14: Ensure that all European public services are accessible to all citizens, including persons with disabilities, the elderly and other disadvantaged groups. For digital public services, public administrations should comply with e-accessibility specifications that are widely recognised at European or international level.
2.9 Underlying principle 8: security and privacy
Citizens and businesses must be confident that when they interact with public authorities they are doing so in a secure and trustworthy environment and in full compliance with relevant regulations, e.g. the Regulation and Directive on data protection , and the Regulation on electronic identification and trust services . Public administrations must guarantee the citizens’ privacy, and the confidentiality, authenticity, integrity and non-repudiation of information provided by citizens and businesses. Security and privacy are discussed in more detail in section 4.3.7.
Recommendation 15: Define a common security and privacy framework and establish processes for public services to ensure secure and trustworthy data exchange between public administrations and in interactions with citizens and businesses.
2.10 Underlying principle 9: multilingualism
European public services can potentially be used by anyone in any Member State. So multilingualism needs to be carefully considered when designing them. Citizens across Europe often have problems in accessing and using digital public services if these are not available in the languages they speak.
A balance needs to be found between the expectations of citizens and businesses to be served in their own language(s) or their preferred language(s) and the ability of Member States’ public administrations to offer services in all official EU languages. A suitable balance could be that European public services are available in the languages of the expected end-users, i.e. the number of languages is decided on the basis of users’ needs, such as the level to which the service is critical for the implementation of the digital single market or national policies, or the size of the relevant audience.
Multilingualism comes into play not just in the user interface, but at all levels in the design of European public services. For example, the choices made on data representation in an electronic database should not limit its ability to support different languages.
The multilingual aspect of interoperability becomes also relevant when a public service requires exchanges between information systems across language boundaries, as the meaning of the information exchanged must be preserved.
Recommendation 16: Use information systems and technical architectures that cater for multilingualism when establishing a European public service. Decide on the level of multilingualism support based on the needs of the expected users.
2.11 Underlying principle 10: administrative simplification
Where possible, public administrations should seek to streamline and simplify their administrative processes by improving them or eliminating any that does not provide public value. Administrative simplification can help businesses and citizens to reduce the administrative burden of complying with EU legislation or national obligations. Likewise, public administrations should introduce European public services supported by electronic means, including their interactions with other public administrations, citizens and businesses.
Digitisation of public services should take place in accordance with the following concepts:
- digital-by-default, whenever appropriate, so that there is at least one digital channel available for accessing and using a given European public service;
- digital-first which means that priority is given to using public services via digital channels while applying the multi-channel delivery concept and the no-wrong-door policy, i.e. physical and digital channels co-exist.
Recommendation 17: Simplify processes and use digital channels whenever appropriate for the delivery of European public services, to respond promptly and with high quality to users’ requests and reduce the administrative burden on public administrations, businesses and citizens.
2.12 Underlying principle 11: preservation of information
Legislation requires that decisions and data are stored and can be accessed for a specified time. This means that records  and information in electronic form held by public administrations for the purpose of documenting procedures and decisions must be preserved and be converted, where necessary, to new media when old media become obsolete. The goal is to ensure that records and other forms of information keep their legibility, reliability and integrity and can be accessed as long as needed subject to security and privacy provisions.
To guarantee the long-term preservation of electronic records and other kinds of information, formats should be chosen to ensure long-term accessibility, including preservation of associated electronic signatures or seals. In this regard, the use of qualified preservation services, in line with Regulation (EU) 910/2014, can ensure the long-term preservation of information.
For information sources owned and managed by national administrations, preservation is a purely national matter. For information that is not strictly national, preservation becomes a European issue. In that case, an appropriate ‘preservation policy’ should be applied by the Member States concerned, to cope with any difficulties arising if the relevant information is used under different jurisdictions.
Recommendation 18: Formulate a long-term preservation policy for information related to European public services and especially for information that is exchanged across borders.
2.13 Underlying principle 12: assessment of effectiveness and efficiency
There are many ways to take stock of the value of interoperable European public services, including considerations such as return on investment, total cost of ownership, level of flexibility and adaptability, reduced administrative burden, efficiency, reduced risk, transparency, simplification, improved working methods, and level of user satisfaction.
Various technological solutions  should be evaluated when striving to ensure the effectiveness and efficiency of a European public service.
Recommendation 19: Evaluate the effectiveness and efficiency of different interoperability solutions and technological options considering user needs, proportionality and balance between costs and benefits.