IoT technology has redefined the way we live, work, and interact. It is transforming CRM business operations, collaboration at workplaces, analysis of data among other things. However, at its core, it is a complex system that involves a lot of layers and protocols. It is essential to break down the IoT environment and provide clear descriptions and definitions so that the whole IoT system can be simplified. The scope of this blog is limited to the IoT reference model but you will learn everything you need to know in layman language. Let’s get started-
What Is the IoT Reference Model?
The main purpose of the reference model is creating a common grounding and language for IoT systems and architectures. It comprises all the references and concepts based on which IoT architectures can be developed. The model consists of all the submodels that establish the complete scope of the IoT design space. It is important to understand that it does not limit the locality or the overall scope of the components.
The model enables processes that are happening at every IoT levels to vary from simple to complex depending on the situation. It comprises how tasks should be managed at each level to provide more supportability and ensure more scalability and simplicity. The foundations of the reference model lie in the IoT domain model. The domain model explores all the main concepts of the Internet of Things. In particular, it describes devices, virtual entities, and IoT services.
Let us briefly see the IoT domain model before going ahead with the IoT reference model.
IoT Domain Model
The domain model is an important aspect of the reference model since it covers all the core definitions of the abstract concepts. It basically provides an abstract representation of all the objects, entities, and concepts in the IoT domain. It describes the features of the objects and establishes relationships between them. The domain model of an IoT system is not dependent on any platform or technology.
It gives system designers some idea about the domain for which the IoT system is to be designed. For a particular home automation system, the objects, concepts, and entities defined under the domain model include: virtual entity, device, resource, physical entity, service, etc. The domain model also serves as a tool for communication for different users working in a particular domain in an IoT ecosystem. It is also the basis of further models like the IoT communication model or information model.
In the next section, check out what are the main devices in the IoT Domain Model-
What Are the Main Devices in the IoT Domain Model?
The devices are the physical objects that enable communication between the virtual and physical world. To know this further, let us explore the three main types of devices that come under IoT domain model-
IoT Sensors-
Sensors can be simple or complex depending on their purpose and generally includes a transducer that converts physical parameters into electrical parameters. Essentially, sensors help in transforming analog signals into digital signals. For example, a video camera can be a great example of complex sensors that can detect motions, unauthorized entry, and recognize people.
Actuators-
These are devices that function opposite to that of sensors. Its main purpose is to convert electrical signals into mechanical motions. Actuators can be used in smart homes to turn on the lights or in industries to switch on the motor. They can be further categorized into the kind of energy they take as input or the kind of motions they can produce. The type of actuators to use also depends on the application requirements such as response time, force level, and the durability.
Tags-
In general, tags recognize the physical identity that they are tethered to. In reality, tags can comprise physical entities or devices but not both. In an IoT ecosystem, the example of a device tag can be RFID, which is Radio Frequency Identification. As a physical entity, the tag can be a quick response code or paper-printed bar code. Electronic devices or paper printed entities involve unique identification that can be recognized by radio signals or optical means.
Now, let’s come back to the IoT Reference Model and explore various levels in it.
Levels in IoT Reference Model
At the 2014 IoT world forum, the seven levels were collectively introduced by IBM, Cisco, and Intel. They are as follows:
Level 1: Controllers and Physical Devices
The reference model begins at level 1 with objects and controllers that can control multiple devices. These can be referred to as “things” in IoT and involve a wide variety of endpoint devices that can send or receive information. The list of these devices and controllers is quite massive in the modern IoT environment. And, it is only going to further improve as more equipment gets introduced in the world of IoT.
Level 2: Connectivity
All the concepts related to communications and connectivity are focused at one level- level 2. The main purpose of level 2 is to facilitate reliable and timely transmission of data. The transmission can happen across networks, between the network and the information processing at a lower level, and between network and devices. There are some legacy devices that are not enabled through IP and might require additional gateways for communication. In other devices, there might be requirements of proprietary controllers to ensure communication. Understanding level 2 is important for implementing efficient protocols like 6LoWPAN in IoT.
Level 3: Edge Computing
In level 3, we deal with conversion of network information into datasets that is more appropriate for higher level processing and storage. This essentially implies that all processes in level 3 primarily deal with transformation and high volume of data analysis. The IoT reference model makes it necessary for smart systems to execute processing close to the network and as early as possible. This is also called fog or edge computing and it mostly occurs in level 3.
Level 4: Data Accumulation
The design of network systems makes them capable of reliably transmitting data. Up to level 3, IoT considers the data to be “in motion” or “always moving.” Level 4 deals with conversion of “moving data” to “rest data”, making it more suitable for memory or disk storage. It checks whether the data is properly organized or not or whether it needs volatile or non-volatile storage. Level 4 also ensures that the data is aggregated or combined with existing data if it needs to be combined.
Level 5 : Data Abstraction
In level 5, the data abstraction focuses on ensuring that the data and storage are suitable for quicker and high-performance applications. Data abstraction involves multiple aspects such as assuring semantics consistently across different devices and assembling and ordering data from diverse sources. Moreover, it also involves verifying that the data is complete and relevant for higher level applications. Additionally, level 5 also deals with data centralization and ensuring access to multiple data stores via data virtualization.
Level 6: Application
It is the application level and mainly deals with interpretation of information. Now, the IoT software need not function at network speeds because it mainly involves communication with level 5 and interaction with data at rest state. If the structure between level 1 to 5 is perfect then the amount of work needed in level 6 vastly reduces. Ensuring the right design in level 6 is significant to allow users to perform their activities faster.
Level 7: Processes and Collaboration
All the intricacies and efficient network within the IoT will not prove to be valuable unless there is definite action at the end. Level 7 deals with collaboration and processes and extensively covers people and the usefulness of IoT. Till level 6, IoT focuses on creating the right data. However, level 7 covers multiple applications and ensures collaboration between the users to make IoT relevant for real-time use. Collaboration in the IoT environment takes place through multiple steps and needs a medium such as the internet for communication.
Conclusion
The main objective of the IoT reference model or reference architecture is to ensure implementation of processing and connectivity between existing networks. It lays out all the functionalities and the issues required to be addressed so that organizations can realize the true value of IoT. The blog explores the functional model in depth and the seven levels through which data is processed. Understanding the reference model is quite crucial before learning more advanced concepts like the conceptual framework of IoT. For more in-depth IoT-related concepts, check out our official website.
