Smart cities are IOT enabled applications which provide services from controlling streetlight according to weather conditions, smart parking vehicles according to free parking slots, up to traffic management according to train arrival time. They also concern access to education, health, cultural and sports services. If all the applications are based on interaction between each other according to the requirement, then it will be great success in achieving robust smart city services. Many services factors such as availability, quality, affordability, and continuity can be increased by enabling communication between the services. This research is focused on communication between different IOT enabled services. Two techniques used here are centralized level interaction and peer level interaction. The task of centralized level interaction is registering all IOT enabled services and sending required information to the respective services in time. Peer level services speak to each other whenever required. This research also analyses advantages and drawbacks of both of these techniques.
TopIntroduction
Smart parking, transport, power and water supply, telecommunication services, public transport and many other services including access to a high-speed internet connection, free Wi-Fi, 4G/5G coverage and many more are part of smart cities. People uses smart city applications such as smart homes, connected cars through smartphones. Sustainability can be improved by pairing systems of infrastructure of smart cities and also cost can be reduced. With the help of smart city communities’ energy distribution can be optimized, traffic congestion can be reduced and air quality can be improved. If the services of the smart city speak each other there will be numerous benefits.
Advantages of communication between services are given here.
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The usage of connected lights of the traffic receive data through sensors and corrects the light to real time traffic thus reducing the congestion of the road.
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Drivers directed to nearest parking slots through connected car services.
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Waste management companies automatically get information to pick-up wastes according to pre-planned timings.
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Smart city services and government services can be accessed through mobile phones of citizens by their digital credentials and ID cards.
In olden days distributed systems were using message queues to handle communication between different parts of system. Huge amounts of data were transferred for massive amounts of activities to the cloud server (Ashu et al, 2021). The model used by traditional system were asynchronous processing architectures which was working in only single direction.
Smart cities’ Internet of things requires different kind of messaging styles and messaging between the services required to follow appropriate protocols and existing network architecture to speed-up the services. To integrate the different components of application stack, messaging models need to be more complex.
One way messaging and 2-way messaging are 2 kinds of messaging models used by IOT-enabled services to interact between server or cloud services. One-way model was asynchronous and to overcome this 2-ways model was used. Sending messages between IOT services to cloud and cloud to IOT services requires 2-way messaging model.
Message brokers/Queue: This allows the queues support from one-to-many connected clients which supports massive huge amounts of big data scenarios () . Identifying, authenticating and addressing of IOT devices are done through message brokers. Among many platform-as-a-service providers such as Azure IoT Hub, Microsoft Azure cloud, IOT message broker service support huge events or telemetry from numerous IOT components. Due to message brokers, the burden of installing up and maintaining virtual machines in the cloud are reduced and it is required to focus on only maintain and building IOT solutions (Renuka et al, 2018).
Benefits of IOT message brokers compared to traditional brokers are
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Device authentication for device management
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Tracking messages from connected IOT devices
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Uniquely addressing IOT devices to support “Cloud-to-Device” messaging model
The proposed system is focussed on 2 kinds of communication between services and messaging models with their architecture. That is centralized message-based system and peer to peer to level messaging system.
The organization of this research paper is as follows; section 2 discusses literature survey, section 3 explains methodology, section 4 focusses on the centralized communication system, section 5 discusses about implementation, section 6 on results, section 7 describes analysis, and finally section 8 mentions about conclusion and future work.
TopLiterature Review
Advantages of P2P based middleware compared to centralized system is made it to use P2P middleware system as proposed by (Genaud et al, 2007) and (W. T. Teacy et.al, 2012). The important task of the P2P MPI is fault-tolerance, scalability, ease of maintenance and resource discovery. When there are large number of IOT services, one of the goal of P2P middleware is scheduling the jobs of IOT services. The performance of middleware is measured by throughput of the system(H. Rajab and T. Cinkelr, 2018) and (J. Wang et. al, 2016).