Physical Design:
In physical design of IoT, we deal with the actual components, protocols and things. Physical design refers to the things and protocols. Following is a list of all the things and protocols involved in the IoT ecosystem:
Things in IoT: Things refer to all the components that relate with each other to perform a certain task. We can categorize all the components in various categories like:
- Connectivity: USB, HDMI, RJ-45
- Processor: CPU
- Graphics: GPU
- Memory: Registers, RAM
- Storage: SD, MMC
- I/O interfaces: UART, I2C (Inter Integrated Circuit), SPI (Serial Peripheral Interface)
Protocols: Many protocols are there in the IoT ecosystem. We can classify them based on either TCP/IP layers or IoT layers. Here we categorize them on TCP/IP layers:
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Link Layer
Protocols of this layer work for the better connectivity and determination of the data transfer from devices to the network.
- IEEE 802.3 (Ethernet): The protocol for establishment and working of a standard wired LAN (10Mbps to 10Gbps).
- IEEE 802.11 (Wi-Fi): The protocol for establishment and working of a standard wireless LAN (1Mbps to 6.75Gbps).
- IEEE 802.16 (Wi-Max): The protocol for establishment and working of a standard wireless MAN (1Mbps to 1Gbps).
- IEEE 802.15.4 (Zigbee): The protocol for establishment and working of standard wireless LANs of LR-WPAN (Low-rate Wireless Personal Area Network) type (40Kbps to 250Kbps).
- 2G/3G/4G: Different cellular telephony generations. (9.6Kbps to 100Mbps)
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Features
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IEEE 802.3 (Ethernet)
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IEEE 802.11 (Wi-Fi)
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IEEE 802.15.4 (Zigbee)
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IEEE 802.16 (Wi-Max)
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Application
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Wired LANs
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Wireless LANs
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Low Power Sensor Networks
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Broadband Wireless Access
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Transmission Media
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TPC, Co-axial, OFC
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Radio Waves
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Radio Waves
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Radio Waves
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Distance Cover
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100m for TPC
180m or 500m for Co-axial
Several Kms for OFC
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Upto 100m
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10m - 100m
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Several Kms
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Data Rate
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10Mbps to 10Gbps
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1Mbps to 6.75Gbps
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40Kbps to 250Kbps
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1Mbps to 1Gbps
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Error Detection
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CSMA/CD
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CRC
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6LowPAN
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AES
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Network Layer
Protocols of this layer work for the better routing and forwarding of data packets along the network.
- IPv4: IPv4 is the addressing scheme used for efficient routing and forwarding of data packets across the network. It is 32-bit in length making it feasible for at least 232 different addresses at a time.
- IPv6: IPv6 is the extended addressing scheme used for routing and forwarding of data packets across the biggest networks. It is 128-bit in length making it feasible for at least 2128 different addresses at a time.
- 6LowPAN: It stands for IPv6 Low Power Personal Area Network. It was the first ever wireless standard written specially for IoT. It provides data rate of about 250Kbps.
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Transport Layer
Protocols of this layer work for the better transfer reachability of data packets along the network.
- TCP: It stands for Transmission Control Protocol. TCP ensures that a reliable path should be created, maintained and destroyed for the transfer of data packets.
- UDP: It stands for User Datagram Protocol. UDP does not ensures any path establishment. Instead, it focuses on resource utilization making all routes available for all the packets.
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Application Layer
Protocols of this layer work for the better utilization of services provided by networks.
- HTTP: It stands for Hyper Text Transfer Protocol. It provides a standard way to transfer documents and their contents in the form of HTML pages.
- CoAP: It stands for Constrained Application Protocol. Very similar to HTTP, CoAP is specific to networks having many end-devices.
- MQTT: It stands for Message Queue Telemetry Transport Protocol. It is a machine to machine (M2M) connectivity protocol that works on client server configuration.
- XMPP: It stands for Extensible Messaging and Presence Protocol. XMPP is an XML based messaging protocol that works for real time message transfer across the devices in IoT.
- AMQP: It stands for Advanced Message Queue Protocol. It enables encrypted real time messaging across the devices and applications.
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Features
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HTTP
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COAP
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MQTT
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AMQP
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XMPP
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Transport
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TCP
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UDP
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TCP
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TCP
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TCP
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Scope
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Device to Cloud
Cloud to Cloud
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Device to Device
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Device to Cloud
Cloud to Cloud
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Device to Device
Device to Cloud
Cloud to Cloud
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Device to Cloud
Cloud to Cloud
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Security
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HTTPS
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DTLS
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TLS
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TLS
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TLS
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Interaction Model
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Request-Response
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Request-Response
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Publish and Subscribe
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Publish and Subscribe
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Request-Response
Publish and Subscribe
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