IOT Unit-II Notes PDF

BCCA Part -III Sem-V IOT UNIT-II IoT Architecture and Protocols: Taxonomy of IoT, Three-layer and five-layer architecture of IoT, cloud and fog-based architecture, representative architecture, NFC, WSN, IoT Network Protocol Stack, Bluetooth, ZigBee and 6LowPAN. IoT Architec...

BCCA Part -III Sem-V IOT UNIT-II IoT Architecture and Protocols: Taxonomy of IoT, Three-layer and five-layer architecture of IoT, cloud and fog-based architecture, representative architecture, NFC, WSN, IoT Network Protocol Stack, Bluetooth, ZigBee and 6LowPAN. IoT Architecture and Protocols: ▪ The Internet of Things (IoT) is the name of multiple electronic devices that are equipped with a unique IP address and communicated over the Internet. ▪ IoT in many ways, but ultimately, with the help of the Internet, we can control the number of electronic devices in this development through a single device. ▪ Here, the sensors should be provided by the electronic devices in IoT technology, and the signal should be sensed electrically and functions accordingly. ▪ The sensed data is transferred via the Internet to the other computer. ▪ For seamless and smooth connectivity between the devices, there is the need for common protocol or architecture that will ensure that devices can communicate to and understand each other across space and time. Taxonomy of IoT: ▪ Taxonomy refers to a process whereby items are named and classified according to their similarities and differences. ▪ In the area of IoT, taxonomy is based on the architectural elements and the protocols of IoT. ▪ Figure depicts the taxonomy of internet of things based on the parameters such as IoT applications, business objectives, enable technologies, platforms and architecture types, networking topologies, and architecture requirements. Session 2024-25 BCCA Part -III Sem-V IOT Three-layer and five-layer architecture of IoT ▪ IoT should be able to connect and transfer data among billions and trillions of devices. For that, it is necessary to have a well-structured and organized architecture. ▪ This architecture is supposed to be capable of accommodating a wide range of components and technologies that form a part of the IoT ecosystem. ▪ The first and most basic three-layer architecture is shown in Figure. ▪ It was established in the initial phases of study in this area. The architecture comprises of three layers, namely, the perception, network, and application layers. Session 2024-25 BCCA Part -III Sem-V IOT Perception Layer: ▪ The perception layer (or object layer/devices layer): The perception is the external layer with sensors for sensing and collecting environmental data. ▪ In the environment, it detects those physical parameters or recognizes certain smart objects. ▪ The physical devices include different types of sensors like the ones based on micro- electromechanical systems (MEMS) technology. ▪ Many different types of Sensors are available for this use like proximity sensors, light sensors, gesture and optical sensors, touch and fingerprint sensors, pressure sensors, and many more. Session 2024-25 BCCA Part -III Sem-V IOT ▪ Standardized plug and play mechanisms are used by the physical layer to consolidate and construct the heterogeneous types of sensors that belong to the IoT device ecosystem. ▪ The data collected at this layer is passed on to the next layer using different network channels. The Network Layer: The network layer provides the link between network devices and servers to create smart devices or IoT. Its features are also used for transmitting and processing sensor data. The data transmission can happen using any of the following technologies: ▪ RFID ▪ 3G ▪ GSM ▪ UMTS ▪ Wi-Fi ▪ Bluetooth low energy ▪ Infrared ▪ ZigBee Specialized processes for handling functions such as cloud computing and data management are also present in this layer. The Application Layer: ▪ The application layer makes it possible to provide specific services to users. ▪ It is that part of the IoT architecture that outlines the various applications for IoT to be deployed, for example, in smart homes and smart health. ▪ This layer is responsible for meeting the various kinds of services requested by users (customers). ▪ The type of service requested by the customer depends on the specific use case that is adopted by the customer. ▪ For example, if a smart home is the use case under consideration, then the customer may request for specific parameters such as heating, ventilation, and air conditioning (HVAC) measurements or temperature and humidity values. ▪ This layer provides the various types of smart services, which are offered by various IoT verticals. Some of the prominent IoT verticals are as follows: Session 2024-25 BCCA Part -III Sem-V IOT ▪ Smart cities ▪ Smart energy ▪ Smart health care ▪ Smart buildings or homes ▪ Smart living ▪ Smart transportation ▪ Smart industry The three-layer architecture defines the main idea of the IoT, but it is not sufficient for research on IoT because research often focuses on finer aspects of the IoT. The five-layer architecture: The five-layer architecture includes the two layers of perception and application, which have been described above. The functions of the other three layers, namely the transport, processing and the business layers are at this moment described below. Figure shows the five-layer architecture of IoT: Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT Application Layer: The application layer manages all application process based on information obtained from middleware layer. This application involves sending emails, activating alarm, security system, turn on or off a device, smartwatch, smart agriculture, etc. Perception Layer: This is the first layer of IoT architecture. In the perception layer, number of sensors and actuators are used to gather useful information like temperature, moisture content, intruder detection, sounds, etc. The main function of this layer is to get information from surroundings and to pass data to another layer so that some actions can be done based on that information. The transport layer: ▪ The transport layer is responsible for transferring sensor’s data from the perception layer to the processing layer and vice versa by means of a variety of connectivity such as RFID, NFC, LAN, Bluetooth, and many more. ▪ As the name suggests, it is the connecting layer between perception and middleware layer. It gets data from perception layer and passes data to middleware layer using networking technologies like 3G, 4G, UTMS, WiFI, infrared, etc. ▪ This is also called communication layer because it is responsible for communication between perception and middleware layer. All the transfer of data done securely keeping the obtained data confidential. The processing layer: ▪ This is where the middleware layer which stores, analysis, and processes a large amount of data in the transport layer architecture. It manages the different services to the lower layers and uses technologies such as databases, cloud computing, and Big Data processing modules to achieve its functions. ▪ Middleware Layer has some advanced features like storage, computation, processing, action taking capabilities. It stores all data-set and based on the device address and name it gives appropriate data to that device. It can also take decisions based on calculations done on data-set obtained from sensors. The Business Layer: ▪ This part of the architecture manages and responsible for the whole IoT system. This layer includes the applications, business and the profit models as well as user privacy. ▪ It performs the overall management of all IoT activities and services. This layer uses the data that are received from the network layer to build various components such as business models, graphs, and flowcharts. Session 2024-25 BCCA Part -III Sem-V IOT ▪ This layer also has the responsibility to design, analyze, implement, evaluate, and monitor the requirements of the IoT system. ▪ This layer can use big data analysis to support decision-making activities. This layer also performs a comparison of obtained versus expected outputs to enhance the quality of services. ▪ The success of any device does not depend only on technologies used in it but also how it is being delivered to its consumers. Business layer does these tasks for the device. It involves making flowcharts, graphs, analysis of results, and how device can be improved, etc. Cloud and fog-based architecture of IoT: ▪ Fog based architecture or also known as fog networking uses edge devices to perform a significant amount of computation, storage, and communicate locally over the Internet backbone. ▪ Fog in IoT utilizes a decentralized computing infrastructure in which data storage, computing, and applications are located somewhere between the data source and the cloud. ▪ Thus, it makes it possible to bring the benefits of the cloud closer to where data is created or produced and acted upon. ▪ In recent times, the trend is to advocate for Fog computing as system architecture. In this respect, sensors and network gateways are used in data processing and analytics. ▪ This type of architecture offers a layered approach that covers areas of control, storage, and protection between the physical and transport layers, while the monitoring layer takes control of the power, resources and services. ▪ The cloud platform receives and aggregate data summaries from many fog nodes, and it also performs analysis on IoT data and data from other sources to gain business insight. Cloud computing architecture can send new application rules to the fog nodes: Session 2024-25 BCCA Part -III Sem-V IOT ▪ Figure describes how data is being processed between fog and cloud-based architecture. ▪ The left part of the figure shows the cloud layer which consists of three layers, at the center is cloud layer, above the cloud layer is an application of layers and below the cloud layer is a network of things layer. ▪ The right side of the figure describes the fog-based architecture of IoT. ▪ It consists of six layers physical, transport, security, monitoring, pre-processing, and storage. Fog based architecture: ▪ Fog based architecture presents a layered approach which inserts monitoring, pre- processing, storage and security layers between the physical and transport layers. ▪ Fog based architecture is also known by another name that is edge-based architecture. Fog based architecture is an advanced version of cloud-based architecture. ▪ Fog computing acts on IoT data in milliseconds, based on policy and sends selected data to the cloud for long–term storage. Fog computing performance is better than cloud computing for handling user request. Fog computing has flexible infrastructure. ▪ In fog-based structure, response time is low, Unlimited number of users as well as resources. Besides sending a vast amount of data to the cloud, it analyzes most time- sensitive data at the network edge. Mainly fog architecture considered only the four layers, that is, the following layers of fog architecture are: Monitoring layer: ▪ It performs the monitoring functions like check the availability of resources and requirement of services by the clients and various responses. Session 2024-25 BCCA Part -III Sem-V IOT Pre-processing layer: ▪ It helps in analyzing the data by doing filtering processes. Storage layer: ▪ The data from the pre-processing layer is sent to the storage layer. It helps in storage in a different format as per requirement and needs with suitable protocols. Security layer: ▪ It helps in offering privacy status to the data flow as well as helpful in the encryption and decryption of data. ▪ The most time-sensitive data are analyzed on the fog node closest to the things generating the data. ▪ In a Cisco Smart Grid distribution network, for example, the most time-sensitive requirement is to verify that protection and control loops are operating properly. ▪ Therefore, the fog nodes closest to the grid sensors can look for signs of problems and then prevent them by sending control commands to actuators. ▪ Data that can wait seconds or minutes for action is passed along to an aggregation node for analysis and action. In the Smart Grid example, each substation might have its aggregation node that reports the operational status of each downstream feeder and lateral. ▪ Data that is less time-sensitive is sent to the cloud for historical analysis, big data analytics, and long-term storage (see sidebar). ▪ For example, each of thousands or hundreds of thousands of fog nodes might send periodic summaries of grid data to the cloud for historical analysis and storage. Session 2024-25 BCCA Part -III Sem-V IOT Advantages of fog computing ▪ Greater business agility: Developers with proper skills and tools develop applications and market them according to the requirement or demand. Fog applications help in operating the machinery and tools in the way of customer requirement. ▪ Better security: With the proper privacy and along with the cybersecurity solutions, protect fog nodes for better security by using the proper procedures as well as using the same policy. ▪ Deeper insights, with privacy control: Fog computing analyze sensitive data locally instead of sending it to the cloud for analysis. ▪ Lower operating expense: It Conserves network bandwidth by processing selected data locally instead of sending it to the cloud for analysis. Representative architecture ▪ Social Internet of Things (SIoT) is that part of an IoT which is capable of establishing social relationships with other objects with respect to humans. ▪ SIoT, attempts to moderate the challenges of IoT in the areas of scalability, trust, and resource discovery by taking a cue from social computing. ▪ Representative architecture is a part of the social Internet of things that provides such as navigation where one device is initialized and through it, we can navigate to other connected devices and linked back to the start device thereby creating autonomous relationships between objects and humans. ▪ Representative architectures come under social internet of things have a server-side architecture which consist of mainly two-layered approach first one is network layer which constitutes cellular networks, WLAN, internet, and many more, and the second layer is further divided into three parts, that is, base sublayer, component sublayer, and interface sublayer, where base sub-layer constitutes data/metadata and semantic engines, component sublayer consist of profiling, TM, and more, and interface sublayer constitutes applications, human interfaces, object interfaces, and service API’s. ▪ The server connects to all the interconnected components, composes the services, and acts as a single point of service for users. Session 2024-25 BCCA Part -III Sem-V IOT Basic components of SIoT: ▪ IoT requires many devices to be interoperable for the model to function well. The following are some of the major components that enable SIoT applications to be successful: ▪ ID: This refers to the unique method of object identification which is assigned to objects in a typical system. Examples of an ID include MACID, IPv6ID, universal product and other custom methods. ▪ Meta-information: This describes the form and operations of a device in a system. It is needed to establish relationships with other devices as placing them appropriately within the universe of IoT devices. ▪ Security controls: This is synonymous to friend list on Facebook, where an owner of the device puts some restrictions regarding how some devices can connect to them. It is sometimes also known as owner controls. Service discovery: Similar to a system like a service cloud, dedicated directories are created to store details of devices that provide certain kind of services. Keeping the directories up to date make it possible for devices to learn about other devices. Relationship management: This refers to the relationship between devices and how they are managed. For example, storing the relationship between the light controller and a light sensor. ▪ The Social Internet of Things (SIoT) is that part of an IoT which is capable of establishing social relationships with other objects with respect to humans. ▪ SIoT, attempts to moderate the challenges of IoT in the areas of scalability, trust, and resource discovery by taking a cue from social computing. ▪ Representative architecture is a part of the social Internet of things that provides such as navigation where one device is initialized and through it, we can navigate to other connected devices and linked back to the start device thereby creating autonomous relationships between objects and humans. Service composition: ▪ This part of the module in the SIoT provides better-integrated services to users. It allows the system to establish a relationship with an analytics engine where large data that are generated are analyzed to learn about the usage pattern for further improved output or services. ▪ Thus, it is possible to identify users based on say three categories of heavy, medium and low energy consumers in their community or among their Facebook friends. Session 2024-25 BCCA Part -III Sem-V IOT ▪ Figure describes the social IoT architecture, which consists of server-side along with the client, in SIoT server, there are two layers network layer and application layer. ▪ The other side consists of a gateway and object, the gateway and object are further divided into three layers that are sensing layer, network layer, and application layer. Session 2024-25 BCCA Part -III Sem-V IOT ▪ The server-side architecture primarily features three main levels. ▪ There is the base layer that stores the database of all devices including their attributes, meta-information and relationships, then the second layer that contains the code to interact with the other devices, querying their status as well as using some of the subset to affect their service and finally the topmost layer which the application layer providing services to users. ▪ The object-side has two layers namely a first layer which allows devices to connect through standardized protocols and exchange information and the social layer which manages the execution of applications and interacts with the application layer of the server. Near Field Communication (NFC) ▪ Near Field Communication (NFC) is a short-range wireless connectivity standard (Ecma-340, ISO/IEC 18092) that uses magnetic field induction to enable communication between devices when they're touched together or brought within a few centimeters of each other. ▪ Jointly developed by Philips and Sony, the standard specifies a way for the devices to establish a peer-to-peer (P2P) network to exchange data. ▪ After the P2P network has been configured, another wireless communication technology, such as Bluetooth or Wi-Fi, can be used for longer-range communication or for transferring larger amounts of data. ▪ NFC is used in the following ways: ▪ You could take pictures with a cell phone with a built-in camera, and touch an enabled computer or television set to transmit the images for display. ▪ You could download applications or games to a handheld device by touching the computer. ▪ In conjunction with another wireless technology, you could transfer large files between two devices, such as a laptop and a desktop, simply by touching the two together. ▪ Google launched Google wallet sometime back that could support MasterCard PayPass, PayPal, and offers money transfers between smartphones. ▪ As the technology grows, more NFC compatible smartphones will be available and more stores will offer NFC card readers for customer convenience. Types of NFC Passive NFC devices: Session 2024-25 BCCA Part -III Sem-V IOT These near-field communication devices include tags and other small transmitters that can send information to other NFC devices without the need for a power source of their own. These devices don’t really process any information sent from other sources, and can not connect to other passive components. These often take the form of interactive signs on walls or advertisements. Active NFC devices: These near-field communication devices can do both things i.e. send and receive data. They can communicate with each other as well as with passive devices. Smartphones are the best example of active NFC devices. Card readers in public transport and touch payment terminals are also good examples of the technology. Wireless sensor network (WSN) Wireless sensor network (WSN) is the combination of a large small-sized sensor combined witlessly. They are connected to increase the processing power. There is a base station which controls all the devices. They as an individual, have very less processing power and consume less power. They are used in the field of habit monitoring, security and military, collect real-time data, and many more. In Figure there are many devices which are connected by various sensors. These sensors are connected to the base station. The base station receives the information from the sensors and processes it for achieving a particular task. Various models or processing are running on the base station, which provides the useful information: In the above Figure there are many devices which are connected by various sensors. These sensors are connected to the base station. The base station receives the information from the sensors and processes it for achieving a particular task. Various models or processing are running on the base station, which provides the useful information. Now it comes to mind how these can be utilized by connecting to the cloud? The major protocol used for connecting the base station to the AWS cloud is MQTT protocol. Session 2024-25 BCCA Part -III Sem-V IOT IoT network protocol stack IoT stands for things on the internet. IoT is rising at a very rapid rate in the current scenario. IoT is an emerging tool with the advancement of technology that provides a connection between industry, start-ups, and government. The relationship between government, start-ups, and industry is shown in Figure When we talk about the relationship between the industries, then there come various problems which the industry could face while using the IoT stack. There are many security issues which come when we are dealing with the IoT. There are various protocols on various layers when we compare them based on architecture. The main and most important layers are transport layer, and internet layer as only these two layers are majorly responsible for the transfer of information from one location to another. Session 2024-25 BCCA Part -III Sem-V IOT Most of the bugs and attacks are also made on this layer. For example, if we are transferring the data between two machines then while transferring the data, an attacker can intercept the data in between if the connection is not secure by using man in the middle attack. Let’s discuss the function of each protocol in detail. ▪ The connection is made with the help of all the layers shown in the above The network layer comes at the action at first. After the allocation of MAC address of the machine, then the packet is sent to the internet layer. ▪ At internet layer, an IP address is routed to an appropriate channel with the help of IP routing, once routing is done, Transport layer transport the packet from one location to the destination with the help of UDP as well as TCP protocols. ▪ TCP provides safe transfer of data while UDP provides fast transfer of data, the protocol is selected based on the requirement of the system. while the data is reached the destination, there are few application layer protocols which are designed for specific tasks, for example, MQTT protocol transfers the data to the Amazon cloud. Session 2024-25 BCCA Part -III Sem-V IOT ▪ This protocol is specifically made by Amazon for its cloud service. After the data is reached in the application layer, it can be used by the various application used in the field of IoT. IoT technology stack: Every IoT project is having set of interconnected components like hardware, software, communication, cloud and applications. Various components of an IoT project and their interconnection are shown below in Figure. Device hardware ▪ The device hardware is the most basic part of the IoT project. We have to choose the IoT device according to the needs of the type of work we are doing. ▪ If we are doing any complex task we have to use more complex hardware as if we are using raspberry-pi we have sufficient memory, but if we replace Raspberry-Pi with the Arduino, the Arduino may not work properly. More importantly, we have to take a look at our needs before deciding the hardware we need. Device software ▪ Device software is also a very important part of the IoT technology stack. The software provides a mind to the hardware. ▪ There are various types of operating system like Linux, Windows, Solaris, Brillo, and more, which can be used as a base for running different softwares on it. ▪ For example, you want to use the hardware to the maximum then you should run Linux as Linux is very close to the machine it can talk to the machine in a more effective way as the other operating systems. Thus, this solely depends upon the type of function performed. Session 2024-25 BCCA Part -III Sem-V IOT Communication Communication is a method of exchanging information. This is most important to choose it carefully. Communication should be decided according to the topology of the system, such as number of sensors in the IoT project, how these sensors should communicate with each other in a sink or they have to connect with single server it completely depends upon the architecture of the IoT project. Cloud platform This platform is the backbone of the IoT platform. This is further divided into various parts: Analytics: Analytics refers to search the data from the large chunk of data and finding the patterns from the data. This is the most crucial part as if we are not able to find the appropriate data from the large chunk of data, then it will be difficult to process the data. Cloud API’s: API stands for application program interface. These are the interfaces between the service which we want to use and the device. They control the usage. This also provides a facility to process the data in the real-time. Cloud applications There are various applications of the cloud. It provides services like storage to the device. Applications can be developed using cloud-based or web-based. Figure depicts the devices such as mobile phone, laptops, connected cars etc. that are communicating through cloud-based applications. These depend upon the requirements of the user client. These are of internal facing or customer-centric: Session 2024-25 BCCA Part -III Sem-V IOT Bluetooth, ZigBee, and 6LowPAN: ▪ Communication between IoT devices is a big challenge, because of the mobility and low power capacity of the IoT nodes. ▪ Therefore most of the IoT devices communicate through low power wireless technologies for communication. Most of the IoT devices communicate through either a Bluetooth, ZigBee or 6LowPAN. Bluetooth ▪ Bluetooth is a wireless technology that covers the small distance to link different devices like mobiles, laptops and other network devices. ▪ We use it for transfer files or to transfer a small amount of data. We use this technology over short-range that are, 50-150m and device must have Bluetooth 4.2 core specification with a basic data rate of 1Mbps. ▪ It uses Ultra High-Frequency radio waves from 2.4-2.485GHz. We find Bluetooth technology in smartphones, smartwatches, laptops, wireless speakers and wireless headsets. ▪ A master-slave interconnection between Bluetooth devices are shown below in Figure. Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT 1.Radio (RF) layer: It performs modulation/demodulation of the data into RF signals. It defines the physical characteristics of bluetooth transceiver. It defines two types of physical link: connection-less and connection-oriented. 2. Baseband Link layer: It performs the connection establishment within a piconet. 3. Link Manager protocol layer: It performs the management of the already established links. It also includes authentication and encryption processes. 4. Logical Link Control and Adaption protocol layer: It is also known as the heart of the bluetooth protocol stack. It allows the communication between upper and lower layers of the bluetooth protocol stack. It packages the data packets received from upper layers into the form expected by lower layers. It also performs the segmentation and multiplexing. 5. OBEX: It is short for Object Exchange. It is a communication protocol to exchange objects between 2 devices. 6. WAP: It is short for Wireless Access Protocol. It is used for internet access. 7. TCS: It is short for Telephony Control Protocol. It provides telephony service. 8. Application layer: It enables the user to interact with the application. Session 2024-25 BCCA Part -III Sem-V IOT Advantages: ▪ Low cost. ▪ Easy to use. ▪ It can also penetrate through walls. ▪ It creates an adhoc connection immediately without any wires. ▪ It is used for voice and data transfer. Disadvantages: It can be hacked and hence, less secure. It has slow data transfer rate: 3 Mbps. It has small range: 10 meters. ZigBee ▪ ZigBee is a wireless technology used for small scale projects. ZigBee is based on the IEEE 802.15.2 protocol. We use this technology over a small range, that is, 10-100m. ▪ ZigBee is a Personal Area Network task group with low-rate task group 4. It is a technology of home networking. ZigBee is a technological standard created for controlling and sensing the network. ▪ ZigBee is an open, global, packet-based protocol designed to provide an easy-to-use architecture for secure, reliable, low power wireless networks. Flow or process control equipment can be place anywhere and still communicate with the rest of the system. ▪ This technology is operating at 2.4GHz and exchanges data at low data rates, that is, 250kbps over a short area. This technology has various applications in agriculture, automotive sensing, smart homes, remote control, and many more. ▪ ZigBee network has various types of topologies-star, mesh (peer to peer) and cluster tree topology, as shown in the figure below: Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT ▪ Instar network we are having ZigBee coordinator at the center from where the communication starts and all the devices are connected to it. ▪ Each ZigBee device communicates with the coordinator. If any device wants to send any packet to another device, then it must go through the coordinator, two devices can connect only through the coordinator. ▪ We use this topology in personal computers, toys, home automation etc. In peer to peer or mesh topology, we have a single ZigBee coordinator while more than one number of routers and the end devices. ▪ In this number of devices helps to increase the size and one device connect to others if they are in the range of one another. ▪ In this message or packet passes through multiple hops to reach the destination. If any device fails, then this topology uses another path to reach the destination. ▪ We use this topology in industrial control and monitoring, WSN, and more. ▪ In a cluster tree network, we have central coordinate, and nodes that are connected to this center node are known as children. Parent with children makes cluster, and there is number of clusters in this topology. ▪ Communication is only possible if two nodes are directly connected; no two nearby nodes communicate directly. Each cluster must have their ID, that is, Cluster ID. This topology covers a largearea. ZigBee consist of various layers that are shown in the following diagram: Types of ZigBee Devices: Zigbee Coordinator Device: It communicates with routers. This device is used for connecting the devices. Zigbee Router: It is used for passing the data between devices. Zigbee End Device: It is the device that is going to be controlled. General Characteristics of Zigbee Standard: Low Power Consumption Low Data Rate (20- 250 kbps) Short-Range (75-100 meters) Network Join Time (~ 30 msec) Support Small and Large Networks (up to 65000 devices (Theory); 240 devices (Practically)) Low Cost of Products and Cheap Implementation (Open Source Protocol) Extremely low-duty cycle. 3 frequency bands with 27 channels. Session 2024-25 BCCA Part -III Sem-V IOT ▪ In the figure shown above, we see the physical layer (PHY) that is base layer use for modulation and modulation of incoming/outgoing signals. ▪ Medium Access Layer (MAC) is above the PHY layer. This layer use carrier senses multiple access collision avoidance (CSMA) to access the network to transfer data. ▪ Network layer (NEW) is above the MAC layer, and it starts a network, route discovery, check connection and disconnection. ▪ Application Support (APS) sublayer use for data managing services. Application Framework provides a key value pair and generic message services. Session 2024-25 BCCA Part -III Sem-V IOT Physical layer: The lowest two layers i.e the physical and the MAC (Medium Access Control) Layer are defined by the IEEE 802.15.4 specifications. The Physical layer is closest to the hardware and directly controls and communicates with the Zigbee radio. The physical layer translates the data packets in the over-the-air bits for transmission and vice-versa during the reception. Medium Access Control layer (MAC layer): The layer is responsible for the interface between the physical and network layer. The MAC layer is also responsible for providing PAN ID and also network discovery through beacon requests. Network layer: This layer acts as an interface between the MAC layer and the application layer. It is responsible for mesh networking. Application layer: The application layer in the Zigbee stack is the highest protocol layer and it consists of the application support sub-layer and Zigbee device object. It contains manufacturer-defined applications. Features of Zigbee: 1. Stochastic addressing: A device is assigned a random address and announced. Mechanism for address conflict resolution. Parents node don’t need to maintain assigned address table. 2. Link Management: Each node maintains quality of links to neighbors. Link quality is used as link cost in routing. 3. Frequency Agility: Nodes experience interference report to channel manager, which then selects another channel. 4. Asymmetric Link: Each node has different transmit power and sensitivity. Paths may be asymmetric. 5. Power Management: Routers and Coordinators use main power. End Devices use batteries. Advantages of Zigbee: 1. Designed for low power consumption. 2. Provides network security and application support services operating on the top of IEEE. 3. Zigbee makes possible completely networks homes where all devices are able to communicate and be 4. Use in smart home 5. Easy implementation 6. Adequate security features. Session 2024-25 BCCA Part -III Sem-V IOT Disadvantages of Zigbee: 1. Limited range: Zigbee has a relatively short range compared to other wireless communications protocols, which can make it less suitable for certain types of applications or for use in large buildings. 2. Limited data rate: Zigbee is designed for low-data-rate applications, which can make it less suitable for applications that require high-speed data transfer. 3. Interoperability: Zigbee is not as widely adopted as other IoT protocols, which can make it difficult to find devices that are compatible with each other. 4. Security: Zigbee’s security features are not as robust as other IoT protocols, making it more vulnerable to hacking and other security threats. Architecture of Zigbee: Zigbee architecture is a combination of 6 layers. 1. Application Layer 2. Application Interface Layer 3. Security Layer 4. Network Layer 5. Medium Access Control Layer 6. PhysicalLayer Zigbee Applications: 1. Home Automation 2. Medical Data Collection 3. Industrial Control Systems 4. meter reading system 5. light control system 6. Commercial 7. Government Markets Worldwide 8. Home Networking Session 2024-25 BCCA Part -III Sem-V IOT 6LowPAN 6LoWPAN, an IPv6 acronym for low-power wireless personal area networks, is a popular wireless communication standard. 6LoWPAN makes interaction over the protocol of IEEE 802.15.4 using IPv6. This standard establishes a layer of adaptation between the 802.15.4 layer of communication and the layer of transport. 6LoWPAN devices can communicate on the Internet with any other IP-based device. It combines the latest internet protocol IPV6 and low power wireless personal area networks. So,6Lowpan allows the smallest device with limited processing ability to transmit information wirelessly on the internet using IPV6. 6LowPan is low-cost, short range, low memory usage, low bit rate and comprises of edge router & sensor nodes. Using 6Lowpan, the smallest of the IOT devices can be part talk to the outside world.(LED Streetlights) IPv6's choice is due to the large addressing space in IPv6. 6LoWPAN networks connect to the Internet via a gateway (WIFI or Ethernet), which also supports conversion protocols between IPv4 and IPv6 since today's Internet is predominantly IPv4. Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT ▪ 6LoWPAN is an IPv6 protocol, and It’s extended from IPv6 over Low Power Personal Area Network. As the name itself explains the meaning of this protocol is that this protocol works on Wireless Personal Area Network. ▪ WPAN is a Personal Area Network (PAN) where the interconnected devices are centered around a person’s workspace and connected through a wireless medium. You can read more about WPAN at WPAN. ▪ 6LoWPAN allows communication using the IPv6 protocol. IPv6 is Internet Protocol Version 6 is a network layer protocol that allows communication to take place over the network. It is faster and more reliable and provides a large number of addresses. Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT Extra Topics: Fog Computing Fog computing also known as fog networking or fogging, is a decentralized computing architecture that brings cloud computing capabilities to the network’s edge. This method intends to increase efficiency, minimize latency, and improve data processing capabilities. Fog computing is a decentralized computing infrastructure or process in which computing resources are located between the data source and the cloud or any other data center. What is Fog Computing? Fog Computing is the term introduced by Cisco that refers to extending cloud computing to an edge of the enterprise’s network. Thus, it is also known as Edge Computing or Fogging. It facilitates the operation of computing, storage, and networking services between end devices and computing data centers. Session 2024-25 BCCA Part -III Sem-V IOT Session 2024-25 BCCA Part -III Sem-V IOT The devices comprising the fog infrastructure are known as fog nodes. In fog computing, all the storage capabilities, computation capabilities, data along with the applications are placed between the cloud and the physical host. All these functionalities are placed more towards the host. This makes processing faster as it is done almost at the place where data is created. It improves the efficiency of the system and is also used to ensure increased security. When to Use Fog Computing? It is used when only selected data is required to send to the cloud. This selected data is chosen for long-term storage and is less frequently accessed by the host. It is used when the data should be analyzed within a fraction of seconds i.e Latency should be low. It is used whenever a large number of services need to be provided over a large area at different geographical locations. Devices that are subjected to rigorous computations and processings must use fog computing. Real-world examples where fog computing is used are in IoT devices Devices with Sensors, Cameras (IIoT-Industrial Internet of Things), etc. Session 2024-25 BCCA Part -III Sem-V IOT Applications of Fog Computing It can be used to monitor and analyze the patients’ condition. In case of emergency, doctors can be alerted. It can be used for real-time rail monitoring as for high-speed trains we want as little latency as possible. It can be used for gas and oils pipeline optimization. It generates a huge amount of data and it is inefficient to store all data into the cloud for analysis. By far, the most commonly used or forms of IoT architecture are the fog and the cloud- based. Fog based architecture is that part of computing which consists of layered approach useful for processing and filtering data. The cloud-based architecture consists of temporary storage and has a small processing unit with some security features. Entities or components communicate over the network using varieties of a set of protocols and standards. For the short-range, low power communication protocols, the most often used are the Radio Frequency Identification (RFID) and Near Field Communication (NFC). Bluetooth, Wi-Fi, and ZigBee are examples of short-range communication protocols. Cloud-based architecture of IoT: Cloud computing provides scalable and flexible services which include information storage options, software tools and analytics, suitable platform, and core infrastructure for the development. It is an extension of cluster and grid computing used to collect resources at one place and utilize them to high-performance computing. It provides three types of services namely; Software as a Service(SaaS), Platform as a Service (PaaS) and Infrastructure as a Service(IaaS). It also provides mobility features for information handling and storage is reloadable from nearby clients. We can also have big data, machine learning as well as data analytics along with cloud computing for more information. The nature of information sensed as well as produced in the form of data by an IoT device. Cloud computing architecture is divided into the following two parts - ▪ Front End ▪ Back End Session 2024-25 BCCA Part -III Sem-V IOT Front End The front end is used by the client. It contains client-side interfaces and applications that are required to access the cloud computing platforms. The front end includes web servers (including Chrome, Firefox, internet explorer, etc.), thin & fat clients, tablets, and mobile devices Front-end is the side that is visible to the client, customer, or user. Front-end pieces include the user interface and the client’s computer system or network that is used for accessing the cloud system. You have probably noticed that different cloud computing systems use different user interfaces — for example, not only can you choose from a variety of web browsers (including Chrome, Safari, Firefox, etc.), but the Google Docs user interface is different than that of Salesforce. Back End The back end is used by the service provider. It manages all the resources that are required to provide cloud computing services. It includes a huge amount of data storage, security mechanism, virtual machines, deploying models, servers, traffic control mechanisms, etc. On the other hand, the back-end pieces are on the side used by the service provider. These include various servers, computers, data storage systems, virtual machines, and programs that together constitute the cloud of computing services. The back-end side also is responsible for providing security mechanisms, traffic control, and protocols that connect networked computers for communication. Session 2024-25 BCCA Part -III Sem-V IOT Components of Cloud Computing Architecture There are the following components of cloud computing architecture - 1. Client Infrastructure Client Infrastructure is a Front-end component. It provides GUI (Graphical User Interface) to interact with the cloud. 2. Application The application may be any software or platform that a client wants to access. 3. Service A Cloud Services manages that which type of service you access according to the client’s requirement. 4. Runtime Cloud Runtime Cloud provides the execution and runtime environment to the virtual machines. 5. Storage Storage is one of the most important components of cloud computing. It provides a huge amount of storage capacity in the cloud to store and manage data. 6. Infrastructure It provides services on the host level, application level, and network level. Cloud infrastructure includes hardware and software components such as servers, storage, network devices, virtualization software, and other storage resources that are needed to support the cloud computing model. 7. Management Management is used to manage components such as application, service, runtime cloud, storage, infrastructure, and other security issues in the backend and establish coordination between them. 8. Security Security is an in-built back-end component of cloud computing. It implements a security mechanism in the back end. 9. Internet The Internet is a medium through which the front end and back end can interact and communicate with each other. Session 2024-25 BCCA Part -III Sem-V IOT Cloud computing offers the following three types of services: i. Software as a Service (SaaS) ▪ It is also known as cloud application services. Mostly, SaaS applications run directly through the web browser means we do not require to download and install these applications. ▪ Consumers interact with the top layer of the cloud, SaaS. ▪ Whereas users view IaaS and PaaS as raw infrastructure and platform building tools/environments, the SaaS layer of the cloud is the finished product as seen through mobile applications, enterprise-level business solutions, and every single app held within the Apple App Store and the Google Play store. Some important example of SaaS is given below – Example: Google Apps, Salesforce Dropbox, Slack, Hubspot, Cisco WebEx. ii. Platform as a Service (PaaS) ▪ It is also known as cloud platform services. It is quite similar to SaaS, but the difference is that PaaS provides a platform for software creation, but using SaaS, we can access software over the internet without the need for any platform. ▪ PaaS is the second layer of the cloud providing developers with the tools needed to build applications/software and the development environment required to build, stage, edit and launch applications. ▪ Much like the IaaS layer of the cloud, PaaS answers a specific need, dev tools, and environments, enabling companies and individual developers to build the products and services they eventually bring to market. ▪ PaaS is built on top of the IaaS layer as it requires RAM, bandwidth, CPU to operate. ▪ Traditional providers of PaaS are Amazon, Cloud Foundry, Long Jump, Rackspace, and Google. PaaS is the middle layer of the cloud which leverages IaaS resources to build SaaS applications. Example: Windows Azure, Force.com, Magento Commerce Cloud, OpenShift. iii. Infrastructure as a Service (IaaS) ▪ It is also known as cloud infrastructure services. It is responsible for managing applications data, middleware, and runtime environments. ▪ IaaS is the primary layer of the cloud providing data center hardware (e.g. servers, nodes, hypervisors) to consumers and companies for a low monthly price. IaaS enables companies to lease servers packed with computing resources like RAM, bandwidth, CPU, and IP, hosted in a remote data center. Session 2024-25 BCCA Part -III Sem-V IOT ▪ Traditional providers of IaaS are Digital Ocean, Amazon, Google, Microsoft, and Rackspace. IaaS is the foundation for PaaS and SaaS. Example: Amazon Web Services (AWS) EC2, Google Compute Engine (GCE), Cisco Metapod. Layered Architecture of Cloud Application Layer 1. The application layer, which is at the top of the stack, is where the actual cloud apps are located. Cloud applications, as opposed to traditional applications, can take advantage of the automatic-scaling functionality to gain greater performance, availability, and lower operational costs. 2. This layer consists of different Cloud Services which are used by cloud users. Users can access these applications according to their needs. Applications are divided into Execution layers and Application layers. 3. In order for an application to transfer data, the application layer determines whether communication partners are available. Whether enough cloud resources are accessible for the required communication is decided at the application layer. Applications must cooperate in order to communicate, and an application layer is in charge of this. 4. The application layer, in particular, is responsible for processing IP traffic handling protocols like Telnet and FTP. Other examples of application layer systems include web browsers, SNMP protocols, HTTP protocols, or HTTPS, which is HTTP’s successor protocol. Session 2024-25 BCCA Part -III Sem-V IOT Platform Layer 1. The operating system and application software make up this layer. 2. Users should be able to rely on the platform to provide them with Scalability, Dependability, and Security Protection which gives users a space to create their apps, test operational processes, and keep track of execution outcomes and performance. SaaS application implementation’s application layer foundation. 3. The objective of this layer is to deploy applications directly on virtual machines. 4. Operating systems and application frameworks make up the platform layer, which is built on top of the infrastructure layer. The platform layer’s goal is to lessen the difficulty of deploying programmers directly into VM containers. 5. By way of illustration, Google App Engine functions at the platform layer to provide API support for implementing storage, databases, and business logic of ordinary web apps. Infrastructure Layer 1. It is a layer of virtualization where physical resources are divided into a collection of virtual resources using virtualization technologies like Xen, KVM, and VMware. 2. This layer serves as the Central Hub of the Cloud Environment, where resources are constantly added utilizing a variety of virtualization techniques. 3. A base upon which to create the platform layer. constructed using the virtualized network, storage, and computing resources. Give users the flexibility they want. 4. Automated resource provisioning is made possible by virtualization, which also improves infrastructure management. 5. The infrastructure layer sometimes referred to as the virtualization layer, partitions the physical resources using virtualization technologies like Xen, KVM, Hyper-V, and VMware to create a pool of compute and storage resources. 6. The infrastructure layer is crucial to cloud computing since virtualization technologies are the only ones that can provide many vital capabilities, like dynamic resource assignment. Datacenter Layer ▪ In a cloud environment, this layer is responsible for Managing Physical Resources such as servers, switches, routers, power supplies, and cooling systems. ▪ Providing end users with services requires all resources to be available and managed in data centers. ▪ Physical servers connect through high-speed devices such as routers and switches to the data center. Session 2024-25 BCCA Part -III Sem-V IOT ▪ In software application designs, the division of business logic from the persistent data it manipulates is well-established. This is due to the fact that the same data cannot be incorporated into a single application because it can be used in numerous ways to support numerous use cases. The requirement for this data to become a service has arisen with the introduction of microservices. ▪ A single database used by many microservices creates a very close coupling. As a result, it is hard to deploy new or emerging services separately if such services need database modifications that may have an impact on other services. A data layer containing many databases, each serving a single microservice or perhaps a few closely related microservices, is needed to break complex service interdependencies. Session 2024-25