Fraunhofer Institute for Open Communication Systems
Fraunhofer Institute for Open Communication Systems

oupPLUS

Smart Cities ICT Reference Architecture

Blick vom Berliner Alexanderplatz Richtung Rotes Rathaus mit beleuchteten Schaufenstern, Menschen und einer fahrenden Straßenbahn
© Philipp Plum / Fraunhofer FOKUS

Reference architectures are understood as guidance or abstract standard models in form of recommendations, terminology or formalized engineering processes. They contain basic components (e.g. interfaces and services) that are used for the design and implementation of complex technical systems and distributed architectures.

With the development of oupPLUS, a Smart Cities ICT (Information and Communication Technology) reference architecture, a central element for the implementation of standardized Smart City concepts in urban environments is envisioned. Successful reference models from the Internet and telecommunication sector, such as the layer models TCP / IP and ISO / OSI, are considered as guiding examples for reference models and architectures of vital importance.

As basis for the research work on oupPLUS, researchers from Fraunhofer FOKUS created a catalog with important insights as well as central challenges. The catalog was worked out in close cooperation with experts from various IT companies and incorporated lessons learned from successful EU projects such as Triangulum or Open Cities.

Objectives of oupPLUS

The most important contribution of oupPLUS is the facilitation of interoperability between components, modules, layers and general artefacts of ICT systems for Smart Cities. For this purpose, the researchers of Fraunhofer FOKUS identify and analyze interfaces between the individual elements and discuss these in the framework of standardization activities with well-known industry partners and market stakeholders.

A high degree of interoperability simplifies the replication of ICT-based solutions among multiple cities. The focus is on the transferability and replication of concepts and components across European urban centers.

Furthermore, oupPLUS:

  • provides the basics for a common and easy understanding of IC technology for urban areas and for existing ICT strategies of (European) cities,
  • identifies and describes standard data sources as well as the users of the respective data,
  • identifies interfaces as well as corresponding formats (e.g. XML / JSON schema, RDF and ontology vocabulary) and protocols (HTTP(S), REST, 6LowPan, ZigBee, COAP, Subscribe Protocol) which are required for the communication between the participating components,
  • describes necessary security measures (e.g. with respect to privacy, integrity, availability, authorization, as well as anonymization)
  • integrates existing concepts and implementations of urban IT systems,
  • facilitates and strengthens the use of Open Source components thereby guaranteeing independence from individual providers/vendors – i.e. avoiding vendor lock-in in cities and communities,
  • considers Open Data as a key element for sharing data and information and
  • enables the standardization (e.g. ISO, DIN, ETSI) of ICT Smart City concepts, e.g. with respect to components and interfaces of the reference architecture.
Overview oupPLUS, Smart Cities IKT Referenzarchitektur: Organizational, Informational, Technical
© Fraunhofer FOKUS
oupPLUS, Smart Cities IKT Referenzarchitektur

The experts at Fraunhofer FOKUS participates at key standardization activities in the domain . They provide insights into their own research and participate with their experience and expertise in the areas of IT and telecommunications, including urban ICT. Significant standardization initiatives are constituted by the “Memorandum of Understanding – Towards Open Urban Platforms for Smart Cities and Communities” of the EIP-SCC, as well as the DIN SPEC 91357 reference architecture model “Open Urban Platform” (OUP). In terms of content, oupPLUS ties in with the OUP reference architecture in order to further develop and standardize ICT concepts for smart cities.

Important Challenges for oupPLUS

Diversity of existing Smart City architectures

Examples of Smart City implementation projects have demonstrated a very broad diversity of ICT solutions, specifications and designs. These individual and partial solutions do not yet constitute a standardized basis which is suitable for describing a generic ICT reference architecture. Nevertheless, they are starting points for the identification of relevant ICT architectural components and approaches. The research effort of Fraunhofer FOKUS aims to combine the achievements of existing Smart City architectures and architectural frameworks (e.g. TOGAF and GWAC) with academic research results.

Complexity of Smart City Systems

A Smart Cities ICT reference architecture should follow a holistic view of a Smart City ecosystem. Challenges arise from the complexity of such systems. They are used in a wide range of application domains – such as transport, energy, health, public safety, education – and demonstrate complex operations and maintenance processes. In addition, the needs of stakeholders from different disciplines and domains must be taken into account. Besides the operational complexity, Smart City systems have to fulfill strict quality requirements for reliability, availability, maintainability, security and privacy.

Identification of appropriate and missing standards

In order to identify both suitable and missing Smart City standards, a clearly defined method for performing a gap analysis was established and implemented.

Identification and specification of abstract, open interfaces

oupPLUS aims to establish guidelines for well-defined open interfaces between the different ICT components. This opens a variety of new possibilities:

  • Interoperability of different solutions in various areas and urban environments,
  • Replication and reuse of Smart City solutions across multiple cities,
  • Participation of small and medium-sized enterprises in an urban ICT eco-system,
  • Using Open Source and avoiding vendor lock-in.