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support the availability and execution of the assets in compliance with their SLA. Moreover, a
continuous integration and delivery possible for each element in the architecture, automated
testing to reduce regression and guarantee quality should support the system to be operational
24/7, and has a close to zero maintenance windows (software upgrades, firmware upgrades).

5.2.7 Communication

Communication in IoT can happen between the sensor/actuator and the gateway or between the
gateway towards the platform or, in some cases (e.g., NB-IoT, LTE), directly from sensor/actuator
to the platform. Communication with the sensor to the gateway (when wireless) is possible in
numerous ways. At this moment, a variety of standards are available; thus, the platform should be
able to handle different protocols (e.g., LoRa, 802.15.4, NB-IoT, Wi-Fi, LTE, GPRS) and be flexible
in order to incorporate future changes. When new components are selected, they should comply
with communication patterns such as:

– Telemetry, where communication flow is one-way from IoT device to gateway.

– Inquiries, where requests from devices looking to gather required information or asking to
initiate activities; for example, devices having their own business logic need input from a central
server.
– Commands, where the system provides execution commands to a device, or a set of devices,
to perform specific activities.

– Notifications where information flows from other systems to a device, or a group of devices, by
sending a broadcast message such as a time-sync message.

5.3 Data management and service requirements

5.3.1 Data management APIs

Access and consumption of data and services through standard and open APIs facilitate the re-
use of solutions, thus avoiding vendor lock-in. Moreover, by providing data publish/subscribe
functionality, sending and receiving data in the system can be simplified and improved. The system
should provide a set of standard and open APIs to track changes and version updates, along with
notification and asset search functions among other capabilities. As a result, the system will be able
to avoid problems and inconsistencies in accessing the resources, while simplifying the access to
the APIs in the marketplace.

5.3.2 Data storage management

The architecture should address the storage of data from platform and usage perspectives. From
a platform point of view, data could be stored in an on-premise system, in a cloud service or in a

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