W. Dimitrov, R. Nikolov, B. Jekov

University of Library Studies and Information Technologies (BULGARIA)
Researchers in the field of IoT orient their efforts to be beneficial to industry which in turn is constantly setting standards for communication to be present in the common language between software and hardware developers, system integrators, and applicants. The interoperability challenges can be overcome with the introduction of standards to help manufacturers produce and sell on the market compatible devices, and to help integrators design open systems.The goal of the article is to explore and research top-down approach for a smart city technical infrastructure aligned with strategy for future development of the municipality. The article can be useful to researchers who are interested in improving technology in the field of Internet of Things. It can also expand the scope of possibilities for integrators of solutions in the field of IoT who have difficulty in assembling IoT systems; developers who need to produce sensors, gateways, and hubs compatible with those of other manufacturers, cloud services providers and other players in the ecosystems of IoT.

We explore and research top-down approach for a smart city technical infrastructure. It requires semantic level interoperability. Common operating picture requires interoperability based on standards and instrumentation tools for decision makers from public services and private sector planning the future stages of a smart city.

The methodology used in the study includes system synthesis and empirical modelling, morphological analysis, an appraisal based on the proven standards, best practices, and experience with real disaster recovery management systems.

One of main goals of Smart City IoT system is giving public safety services. They are Police, Fire Service, Emergency Ambulance and Crisis Management Command and Control centers in case of criminal incidents, мass public events, fire, earthquake, disasters, flooding, traffic jams, industrial pollutions, car or traffic accidents and so on. Common operating picture has got important role for public safety services and the status of critical infrastructure. Sharing that information at multiple layers in the emergency response ecosystem in real time can dramatically improve the response time of the services and save lives. Because of the public importance of this common model, the review of the standards for the IoT that we do is focused on the new opportunities provided by technology for improvement public safety services operations. In view of the choice of strategy for IoT ecosystem future development in the Smart City services we consider that the main challenges to be explored are:
(1) IoT Business Ecosystem interoperability at the higher level where Common Operating Picture is given to the institutions providing public service;
(2) IoT Technical Ecosystem interoperability at the low level, middleware scalability and data formats standardization at the big data layer;
(3) Security by design and through IoT life cycle together with supply chain security maintenance.

Creating modern intelligent systems such as smart city class, it is advisable to use mature protocols that are open and provide seamless interoperability.

This approach in designing large integrated systems can provide a long lifecycle and the necessary levels of continuity in the areas of: •System development; •Technical assistance and maintenance; •Qualification and training of employees involved in the smart city services and development.