The following communication protocols have immediate importance to

consumer and industrial IoTs:

• IEEE 802.15.4
• Zigbee
• 6LoWPAN
• LoRaWAN
• Bluetooth
• NFC
• RFID

1
The landscape of technologies for wireless IoT
connectivity

Source: https://www.embedded.com/the-internet-of-things-myth-the-search-for-a-connectivity-standard/

2
The IoT landscape

Source: https://www.gadgeon.com/blog/what-is-the-right-wireless-technology-for-your-iot-project/

3
Some Real Life Scenarios : Requirements
• For smart cities, smart buildings, etc.,
• Energy Efficiency
• Target battery lifetime: 5 years, or more
• Scalability
• Large network sizes
• Timeliness
• Alert applications, process monitoring, ...
• Reliability
• Wire‐like reliability may be required, e.g., 99.9% or better

4
Features - Zigbee
• Most widely deployed enhancement of IEEE 802.15.4.
• The ZigBee protocol is defined by layer 3 and above. It works with the
802.15.4 layers 1 and 2.
• The standard uses layers 3 and 4 to define additional communication
enhancements.
• These enhancements include authentication with valid nodes,
encryption for security, and a data routing and forwarding capability
that enables mesh networking.
• The most popular use of ZigBee is wireless sensor networks using the
mesh topology.

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Features – Zigbee(Contd.)

• The lower frequency bands use BPSK.

• For the 2.4 GHz band, OQPSK is used.
• The data transfer takes place in 128 bytes packet size.
• The maximum allowed payload is 104 bytes.
• The nature of transmission is line of sight (LOS).
• Standard range of transmission –upto70m.

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Features – Zigbee(Contd.)
• Relaying of packets allow transmission over greater distances.
• Provides low power consumption (around 1mW per Zigbee module)
and better efficiency due to
• adaptable duty cycle
• low data rates (20 -250 kbit/s)
• low coverage radio (10 -100 m)
• Networking topologies include star, peer-to-peer, or cluster-tree
(hybrid), mesh being the popular.

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Zigbee Topologies
• The Zigbee protocol defines three types of nodes:
• Coordinators-Initializing, maintaining and controlling the network. There is
one and only one per network.
• Routers-Connected to the coordinator or other routers. Have zero or more
children nodes. Contribute in multi hop routing.
• End devices -Do not contribute in routing.
• Star topology has no router, one coordinator, and zero or more end
devices.
• In mesh and tree topologies, one coordinator maintains several
routers and end devices.

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Zigbee based Network Topologies

Source:
https://www.researchgate.net/publication/269517670_Design_and_Performance_Analysis_of_Building_Monitoring_System_with_Wireless_Sensor_Networks/figures
?lo=1

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Zigbee Variants :

• Each cluster in a cluster-tree network involves a coordinator through

several leaf nodes.
• Coordinators are linked to parent coordinator that initiates the entire
network.
• ZigBee standard comes in two variants:
• ZigBee
• ZigBee Pro -offers scalability, security, and improved performance utilizing
many-to-one routing scheme.

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 ZigBee
➢ Operations:
▪ Coordinator: acts as a root and bridge of the
network

▪ Router: intermediary device that permit data to

pass to and through them to other devices

▪ End Device: limited functionality to communicate

with the parent nodes

Low cost and available

Zigbee Types
• ZigBee Coordinator (ZC):
•The Coordinator forms the root of the ZigBee network tree and might
act as a bridge between networks.
•There is a single ZigBee Coordinator in each network, which originally
initiates the network.
• It stores information about the network under it and outside it.
• It acts as a Trust Center & repository for security keys.

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Zigbee Types
• ZigBee Router (ZR):
Capable of running applications, as well as relaying information between
nodes connected to it.
• ZigBee End Device (ZED):
• It contains just enough functionality to talk to the parent node, and it cannot
relay data from other devices.
• This allows the node to be asleep a significant amount of the time thereby
enhancing battery life.
• Memory requirements and cost of ZEDs are quite low, as compared to
ZR or ZC.

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Zigbee Network Layer
•The network layer uses Ad Hoc On‐Demand Distance Vector (AODV)
routing.
• To find the final destination, the AODV broadcasts a route request to all its
immediate neighbors.
• The neighbors relay the same information to their neighbors,
eventually spreading the request throughout the network.
•Upon discovery of the destination, a low‐cost path is calculated and
informed to the requesting device via unicast messaging.

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Zigbee Applications
• Building automation
• Remote control (RF4CE or RF for consumer electronics)
• Smart energy for home energy monitoring
• Health care for medical and fitness monitoring
• Home automation for control of smart homes
• Light Link for control of LED lighting
• Telecom services

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Introduction - 6LOWPAN

• 6LoWPAN is IPv6 over Low-Power Wireless Personal Area Networks.

• It optimizes IPv6 packet transmission in low power and lossy network
(LLN) such as IEEE 802.15.4.
• Operates at 2 frequencies:
• 2400–2483.5 MHz (worldwide)
• 902–929 MHz (North America)
• It uses 802.15.4 standard in unslotted CSMA/CA mode.

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Introduction - 6LOWPAN
• Low‐power Wireless Personal Area Networks over IPv6.
• Allows for the smallest devices with limited processing ability to
transmit information wirelessly using an Internet protocol.
• Allows low‐power devices to connect to the Internet.
• Created by the Internet Engineering Task Force (IETF) ‐ RFC5933 and
RFC 4919.

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Features - 6LOWPAN
• Allows IEEE 802.15.4 radios to carry 128‐bit addresses of
• Internet Protocol version 6 (IPv6).
• Header compression and address translation techniques allow the
IEEE 802.15.4 radios to access the Internet.
• IPv6 packets compressed and reformatted to fit the IEEE 802.15.4
packet format.
• Uses include IoT, Smart grid, and M2M applications.

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 LoRaWAN
• The LoRaWAN wireless technology was developed for LPWANs that
are critical for implementing many new devices on IoT networks.

• The term LoRa refers to the PHV layer, and LoRaWAN focuses on the
architecture, the MAC layer, and a unified, single standard for
seamless interoperability. LoRaWAN is managed by the LoRa Alliance,
an industry organization.

• The PHV and MAC layers allow LoRaWAN to cover longer distances
with a data rate that can change depending on various factors. The
LoRaWAN architecture depends on gateways to bridge endpoints to
network servers. From a security perspective, LoRaWAN offers AES
authentication and encryption at two separate layers.
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LoRaWAN (Contd)
• Unlicensed LPWA technologies represent new opportunities for implementing IoT
infrastructures, solutions, and use cases for private enterprise networks, broadcasters,
and mobile and non-mobile service providers.
• The ecosystem of endpoints is rapidly growing and will certainly be the tie-breaker
between the various LPWA technologies and solutions, including LoRaWAN.
• Smart cities operators, broadcasters, and mobile and non-mobile services providers,
which are particularly crucial to enabling use cases for the consumers’ markets, are
addressing the need for regional or national IoT infrastructures.
• As private enterprises look at developing LPWA networks, they will benefit from roaming
capabilities between private and public infrastructures. These can be deployed similarly
to Wi-Fi infrastructures and can coexist with licensed-band LPWA options.
• Overall, LoRaWAN and other LPWA technologies answer a definite need in the IoT space
and are expected to continue to grow as more and more “things” need to be
interconnected.

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 Short Range IoT Solutions

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Introduction - RFID
• RFID is an acronym for “radio‐frequency identification”
• Data digitally encoded in RFID tags, which can be read by a
• reader.
• Somewhat similar to barcodes.
• Data read from tags are stored in a database by the reader.
• As compared to traditional barcodes and QR codes, RFID tag data can
be read outside the line‐of‐sight.

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Features of RFID
• RFID tag consists of an integrated circuit and an antenna.
• The tag is covered by a protective material which also acts as a shield
against various environmental effects.
• Tags may be passive or active.
• Passive RFID tags are the most widely used.
• Passive tags have to be powered by a reader inductively before they
can transmit information, whereas active tags have their own power
supply.

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Working Principle – RFID
• Derived from Automatic Identification and Data Capture (AIDC)
technology.
• AIDC performs object identification, object data collection and
mapping of the collected data to computer systems with little or no
human intervention.
• AIDC uses wired communication
• RFID uses radio waves to perform AIDC functions.
• The main components of an RFID system include an RFID tag or smart
label, an RFID reader, and an antenna.

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RFID - Applications
• Inventory management
• Asset tracking
• Personnel tracking
• Controlling access to restricted areas
• ID badging
• Supply chain management
• Counterfeit prevention (e.g. in the pharmaceutical industry)

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Functionality based IoT Protocol Organization
• Connectivity (6LowPAN, RPL)
• Identification (EPC, uCode, IPv6, URIs)
• Communication / Transport (WiFi, Bluetooth, LPWAN)
• Discovery (Physical Web, mDNS, DNS‐SD)
• Data Protocols (MQTT, CoAP, AMQP, Websocket, Node)
• Device Management (TR‐069, OMA‐DM)
• Semantic (JSON‐LD, Web Thing Model)
• Multi‐layer Frameworks (Alljoyn, IoTivity, Weave, Homekit)

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 RFID: Radio Frequency Identification
➢ Appeared first in 1945
➢ Features:
▪ Identify objects, record metadata or control individual target
▪ More complex devices (e.g., readers, interrogators, beacons) usually connected to a host computer
or network
▪ Radio frequencies from 100 kHz to 10 GHz
➢ Operations:
▪ Reading Device called Reader (connected to banckend network and communicates with tags using RF)
▪ One or more tags (embedded antenna connected to chip based and attached to object)
 Bluetooth
➢ Features:
▪ Low Power wireless technology
▪ Short range radio frequency at 2.4 GHz ISM Band
▪ Wireless alternative to wires
▪ Creating PANs (Personal area networks)
▪ Support Data Rate of 1 Mb/s (data traffic, video traffic)
▪ Uses Frequency Hopping spread Spectrum
➢ Bluetooth 5:
▪ 4x range, 2x speed and 8x broadcasting message capacity
▪ Low latency, fast transaction (3 ms from start to finish) Data Rate 1 Mb/s: sending just small data packets

Class Maximum Power Range

1 100 mW (20 dBm) 100 m
2 2,5 mW (4 dBm) 10 m
3 1 mW (0 dBm) 1m
Bluetooth Role in IoT Technology

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 Wi-Fi
➢ Wireless Alternative to Wired Technologies
➢ Standardized as IEEE 802.11 standard for WLANs

Standard Frequency bands Throughput Range

WiFi a (802.11a) 5 GHz 54 Mbit/s 10 m

WiFi B (802.11b) 2.4 GHz 11 Mbit/s 140 m

WiFi G (802.11g) 2.4 GHz 54 Mbit/s 140 m

WiFi N (802.11n) 2.4 GHz / 5 GHz 450 Mbit/s 250 m

IEEE 802.11ah 900 MHz 8 Mbit/s 100 M