1. Assist. Prof. Rassim Suliyev Zhumaniyaz Mamatnabiyev Week 10
IoT in Industry
Assist. Prof. Rassim Suliyev
Zhumaniyaz Mamatnabiyev
Week 10

2. OUTLINE IoT protocols Application protocols Transport protocols
Network access and physical protocols
Networking topologies
Logical topologies
Physical topologies
Activity

3. IoT protocols overview
The TCP/IP suite is the key communication protocol stack that includes two significant families of protocols for device communications over the network and the Internet. However, new protocols are required to enhance the TCP/IP suite for the IoT environment by providing the communications between resource-constrained devices within the IoT Low-Power and Lossy Networks (LLN).
IoT devices are usually placed in resource-limited environments, such as: 
remote and isolated agricultural applications;
mobile and lightweight medical devices that need be powered for long periods of time in a variety of locations;
outside for smart city applications; and
many other scenarios where there are power and network connection constraints.

4. IoT protocols overview
Also, in most IoT applications, devices are required to be very small in size for implementation, and therefore they must operate on battery, and run on low memory and CPU power with a limited network communication capability. The majority of IoT applications (such as smart cities), contain a large number of low-power, low-data rate, small devices performing the data acquisition process, transmission of information to actuators, and the update of feedback loops. 

5. IoT protocols overview

6. Application protocols
The application protocols such as HTTP and XMPP, traditionally found in the Application layer, are considered to be resource demanding protocols. This does not make them a suitable option for communication in an IoT constrained environment with a large number of connected devices. Therefore, more lightweight protocols are required by the IoT industry to address this problem.
Constrained Application Protocol (CoAP) and Message Queuing Telemetry Transport (MQTT) are the two most popular IoT application protocols [Hanes et al 2017].

7. Constrained Application Protocol (CoAP)
CoAP is based on HTTP protocol and was designed by the IETF Constrained RESTful Environment (CoRE) working group.
The communication between HTTP client and server is performed by using the Representational State Transfer (REST) standard. As REST is a resource demanding standard, the lightweight RESTful interface was designed in CoAP so that resource-constrained devices in IoT networks can use RESTful services [Salman 2015]. Resources are retrieved from the server using URIs/URLs.
CoAP message exchange is done using UDP (User Datagram Protocol) with strong security measures, through the utilisation of the Datagram Transport Layer Security (DTLS) [Hanes et al 2017]. 
Both IPv4 and IPv6 are supported by CoAP, however IPv6 is used in IEEE networks for constrained devices. 

8. Constrained Application Protocol (CoAP)
CoAP performs the two main activities of messaging and request/response [Salman 2015].
There are four types of messages defined in CoAP: 
confirmable (for reliable transmission)
non-confirmable (for unreliable transmission)
piggyback (acknowledgement)
separate (reset) 
And four request/response methods: 
GET (receive)
POST (create)
PUT (update)
DELETE 

9. Constrained Application Protocol (CoAP)
Communication between devices in CoAP can take place using different paths, including same constrained network, different constrained network, to the Internet servers, and proxy network.
CoAP provides multicast support for messaging the group of devices using for IPv4 and FFOX::FD for IPv6. 

10. Message Queuing Telemetry Transport (MQTT)
In 1999, MQTT was introduced by IBM, and by 2013 it was standardised by OASIS [Salman 2015]. 
MQTT is a lightweight protocol specifically suitable for constrained environments - for example, a harsh environment with low bandwidth connection, such as in oil and gas industries. 
MQTT protocol is the publish-subscribe communication framework between the nodes.
The three components of the MQTT network are:
publisher (client);
subscriber (client); and
message broker (server).

11. Message Queuing Telemetry Transport (MQTT)

12. Message Queuing Telemetry Transport (MQTT)
In the example in previous slide: 
The MQTT publisher is a temperature and humidity sensor collecting environmental values and sending them to the MQTT server or message broker. 
The message broker receives and accepts the connection and data. 
Additionally, the message broker manages the subscription processes to transmit the publisher data to a subscriber interested in this data.
By separating the client’s data transmission in the message, the broker subscribers are able to receive only the data they are interested in. 
Information is buffered at the message broker in the case of connection failure, so the publisher and subscriber do not need to be online at the same time. 
A topic string or topic name is used by the message broker to specify a subscriber message. A topic name is divided into one or more levels separated by slash (/). 
For example, in adt/lora/adeunis/0018B A, topic name adt/lora/adeunis is a topic level. 

13. Message Queuing Telemetry Transport (MQTT)
MQTT uses TCP (Transmission Control Protocol) as a reliable protocol for connection and transmission, and can use Transport Layer Security (TLS) for additional security, however TLS will add more overhead to the communications. 
There are three levels of Quality of Service (QoS) in MQTT protocol - click on each of them below for more information:
Publisher’s message is sent to server (message broker) once with no retransmission. Message broker sends the received information to subscriber, which does not respond with acknowledgement. This level of QoS is known as ‘at most once’ delivery.
Is referred to as ‘at least once’ delivery. In this method, the receiver in any transmission (publisher to server, and server to subscriber) acknowledges the received data by using the packet identifier.
In this level, both duplication and loss are examined and eliminated by two-way acknowledgement in each part of the communications, using the packet identifier - however, this increases the overhead. This level of QoS is known as ‘exactly once’ delivery and guarantees the services.

14. CoAP vs MQTT

15. Transport protocols
Both Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are the core protocols for the TCP/IP protocol suite.
However, IoT applications mostly use UDP, TCP, and DTLS as transport layer protocols. Click on each of these below for more information.
UDP is a connectionless protocol with a very low overhead and fast transmission capabilities, but no guarantee for message delivery. It is usually compared to traditional mail delivery, as there is no acknowledgement for receiving a letter. 
TCP is a connection-oriented protocol that guarantees the establishment of a connection between sender and receiver before data transmission. It is similar to a telephone system that requires a full connection between both ends before they can start talking to each other.
DTLS is a transport layer protocol based on Transport Layer Security (TLS). It provides security services for UDP communications.

16. Internet protocols Internet Protocol version 6 (IPv6)
IPv6 is a an upgrade to IP version 4 (IPv4), defined by IETF. It uses 128 bit addresses compared to the 32 bit addresses in IPv4, providing a larger number of addresses with integrated security features to accommodate the rapid growth of Internet users.
6LoWPAN
IPv6 addresses are too long for IoT data frames and methods; standards and protocols are required to encapsulate the IPv6 datagram in small packets. IPv6 over Low power Wireless Personal Network (6LoWPAN) is the first protocol to have successfully encapsulated the IPv6 for IEEE networks [Salman 2015].

17. RPL IPv6 Routing Protocol for Low Power and Lossy Networks (RPL)
IoT routers, like other devices in an IoT environment, are resource constrained. As they are performing in Low Power and Lossy Networks (LLN), there are limitations that make it almost impossible for us to use traditional routing protocols. 
One of the most popular routing protocols is IPv6 Routing Protocol for Low Power and Lossy Networks (RPL).
RPL is a distance vector routing protocol that determines the best route based on the distance between the nodes. 
Routing is done by each and every node in a RPL network at the IP layer. That means all nodes in the network act as routers transmitting the IPv6 packets to the next hop, based on the destination information retrieved from the IPv6 packet header. 
The RPL has two different modes: storing and non-storing. 
RPL uses the Directed Acyclic Graph (DAG) concept to build the network. 
In a Directed Acyclic (no cycles) Graph (pathway), the graph (pathway) cannot cycle round or return to the same node. 
Routing loops and count-to-infinity problems (where messages go round and round loops and do not reach their destination) are addressed in RPL by using the RANK. 

18. Network access and physical protocols

19. Bandwidth and coverage

20. Bluetooth
PAN or Wireless PAN (WPAN) is a network with a small geographical area coverage, for devices such as sensors that require communication within a few metres. The most popular network technologies for PAN among IoT devices are Bluetooth, Zigbee, Z-wave, Thread and 6LoWPAN.
Bluetooth Low Energy (BLE), a version of Bluetooth designed for low-powered devices, can help IoT devices conserve energy by maintaining the devices in sleep mode until they are connected. What makes BLE ideal for IoT applications is the fact that it can rapidly pair and reconnect with devices in six milliseconds (down from six seconds for classic Bluetooth). 
The most common Bluetooth settings are: 
Standard: Bluetooth 4.2 core specification
Frequency: 2.4GHz (ISM)
Range: m (Smart/BLE)
Data Rates: 1Mbps (Smart/BLE)

21. Bluetooth
The figure below illustrates two topologies of Bluetooth technology: star and mesh topologies. Bluetooth mesh is the latest version, and includes ‘many-to-many’ communications for large-scale networking applications such as asset tracking, home and building automation, lighting, beaconing, and smart metering.

22. Bluetooth The advantages of Bluetooth mesh for IoT are:
Extended Range – In a star network topology, devices are connected using master-slave communications, where the devices must be in the same range as the device that acts as the master. 
Self-Healing Networks – Mesh provides autonomous self-healing by allowing multiple paths between a source and destination.
Enhanced Network Reliability – A well-designed and well-implemented mesh network provides exceptional reliability, because it can better route around failures or intermittent connections.
Scalability – In 2020, networks may grow to up to 50 billion devices, and having a single, central connection point will degrade the quality of the network due to the bottleneck. 
Improved Energy Efficiency and Battery Life –  The sizes of sensors are relatively small with smaller-sized batteries. If sensors transmit data frequently, the transmit power becomes an important factor in battery life calculations. A mesh topology enables these devices to use lower transmit power, with powered routers reliably handling the communications.

23. ZigBee
ZigBee is a WPAN protocol for low processing and low power devices. It has a low data rate that is less expensive than Bluetooth and WiFi, and based on IEEE
ZigBee is suitable for infrequent data transmission at low-data rates within a small area, such as buildings. 
ZigBee uses the ISM (Industrial, Scientific and Medical) frequency band, and has a data rate of approximately 250 kbps. 
A microcontroller, ZigBee chips, and radio can add ZigBee compatibility to IoT devices.

24. ZigBee operation
In a ZigBee network, devices can take on three different roles: 
ZigBee coordinator,
ZigBee router, and 
ZigBee client
The ZigBee coordinator is responsible for managing the Zigbee clients, and formation and maintenance of the ZigBee network. Each ZigBee coordinator can connect to eight ZigBee devices, including a combination of clients and routers.
ZigBee routers are used to bridge the data between ZigBee client and ZigBee coordinators when they are far from each other. The figure below shows the three types of ZigBee topologies.

25. ZigBee application profiles
In ZigBee data transmission, there is an application on the different devices that uses a profile for handling the messages. Profiles are responsible for the interoperability of devices from different manufacturers, such as controlling the home lighting fixture produced by one manufacturer, through a wireless switch from another manufacturer.  
There are three types of application profile: public, private, and manufacturing, which are identified by a 16-bit number known as an Application Profile Identification Number. The ZigBee Alliance manages the public profiles, such as home automation. Private profiles have restricted usage and are defined by ZigBee vendors - if they are then published by their owners, they become manufacturer profiles.

26. 6LoWPAN
6LoWPAN can be seen as a combination of two protocols: Internet Protocol version 6 (IPv6) and Low-Power Wireless Personal Network (LoWPAN). 
The required amount of resource consumption in Internet Protocol (IP) must be optimised to make it suitable for the IoT-constrained environment.
In 6LoWPAN, the Adaptation Layer is responsible for packaging and transporting the IP packets from the Internet layer to the Physical layer (Datalink layer and Network layer in OSI model), so the end-to end connection is addressable, and a router can be used for routing tasks.

27. 6LoWPAN
6LoWPAN supports the mesh network and can communicate not only with the network, but also IP-based networks such as WiFi , Ethernet, and sub-1GHz ISM with a bridge device. It also supports Linux, which is good for small OS on resource-constrained devices. 

28. Thread
Thread is a new protocol based on multiple standards, including: IEEE , IPv6, and 6LoWPAN. Like 6LoWPAN, it provides IP-based communications for resource-constrained devices, and can support 250 nodes in a mesh topology, with robust authentication and an encryption system. 
Thread can be enabled on IEEE devices with a software upgrade.

29. NFC
NFC (near-field communication) is designed for safe, contactless, simple, two-way communications between electronic devices, such as a smartphone to a payment device, within 4 to 10 cantimetres.

30. WAN | Sigfox
Sigfox is the pioneer of global IoT networks, with billions of sensors communicating with each other without the need to establish and maintain network connections. Sigfox provides a software-based communications solution, where all the network and computing complexity is managed in the Cloud, rather than on the devices. This drastically reduces energy consumption and the costs of connected devices.
Sigfox has a range between WiFi and cellular. It uses the ISM bands, which are free for use without the need to acquire licenses, to transmit data over a very narrow spectrum to and from connected objects. Sigfox targets many M2M applications that use a small battery and transmit low data rate packets.
For data transmission using WiFi, the range is too short, and transmitting data using cellular networks is costly and uses too much power.  Sigfox uses Ultra Narrow Band (UNB) and is designed to only transmit a low data rate of 10 to 1,000 bits per second. It consumes only 50 microwatts, compared to 5000 microwatts for cellular communication, and can deliver a typical stand-by time of 20 years with a 2.5Ah battery, compared to only 0.2 years for cellular. 

31. Sigfox
The Sigfox network offers a robust, power-efficient and scalable network that can communicate with millions of battery-operated devices across areas of several square kilometres, making it suitable for various M2M applications that are expected to include smart meters, patient monitors, security devices, street lighting and environmental sensors. The Sigfox system uses silicon, which delivers industry-leading wireless performance, extended range, and ultra-low power consumption for wireless networking applications operating in the sub-1GHz band. 
Standard: Sigfox
Frequency: 900MHz
Range: 30-50km (rural environments); 3-10km (urban environments)
Data Rates: bps 

32. LoRa
LoRa targets wide-area network (WAN) applications and is designed to provide low-power WANs with features specifically needed to support low-cost, mobile, secure, bi-directional communication in IoT, M2M and smart city and industrial applications. Optimised for low-power consumption and supporting large networks of devices, data rates range from 0.3 kbps to 50 kbps. 
Public and private networks using this technology can provide coverage that is greater in range compared to that of existing cellular networks. LoRa is backward compatible with the current infrastructure and maintains the life of battery-operated IoT devices. Semtech builds LoRa Technology into its chipsets. These chipsets are then built into the products offered by our vast network of IoT partners and integrated into LPWANs from mobile network operators worldwide.

33. LoRa

34. LoRa
LoRaWAN is a protocol specification built on top of the LoRa technology developed by the LoRa Alliance. It uses unlicensed radio spectrum in the Industrial, Scientific and Medical (ISM) bands to enable low power, wide area communication between remote sensors and gateways connected to the network. LoRaWAN operates in different frequency bands, based on geographical region:
Europe MHz
USA MHz
Australia MHz
China MHz and MHz  (The Things Network 2018)
This standards-based approach to building a LPWAN allows for quick set up of public or private IoT networks anywhere, using hardware and software that is bi-directionally secure, interoperable and mobile, and provides accurate localisation.

35. Networking topologies
A network topology is the arrangement of the elements of a communications network, including its nodes and connecting links.
The topological structure of a network may be depicted physically or logically - we’ll discuss both in a moment.
Terms such as star, bus, ring, and mesh topology describe how the devices in a network are connected together.

36. Types of visual representation
To enable a network to be designed, and then its operation more easily understood, two methods are used to represent the network visually or graphically.
The logical topology uses symbols (icons) to graphically represent the devices.
The symbols usually do not look anything like the actual device, but are a simplified and general representation of what the device does, and not how it physically looks.
Lines are used to represent the connections between devices and the flow of signals and messages.

37. IoT
The network physical topology is usually graphically overlaid on a building floor plan (or city map) and shows the precise location of the devices.
If it is a cabled network, then the actual pathways of the cables connecting the devices are shown on a plan drawn to scale, showing dimensions, and with cable run lengths.
For wireless networks the area of radio coverage is shown with the signal obstructing properties of walls and obstructions also indicated.
It is important to note that the actual physical topology type of a network usually does not resemble the logical topology of that network.

38. Types of visual representation

39. Types of visual representation

40. Logical topologies
The purpose of the logical topology is to explain the operation of the network, but not necessarily how the devices are physically connected together.
Features of a logical topology include:
Symbols
Flow (signal) lines
Layout (arrangement)
Labels and addresses

41. Logical topologies

42. Logical topology types | Star Topology
The devices are connected to a central network node (switch or hub).

43. Extended Star Topology
The nodes of star topologies can be connected to form an extended star topology network.

44. Bus Topology
Devices are connected to a shared common medium.

45. Ring Topology
The devices are connected sequentially in a circle.

46. Full-Mesh Topology
Each device has a direct connection to every other device. Devices using the ZigBee radio system spontaneously organise a mesh network.

47. Partial-Mesh Topology
In some cases, connecting all devices logically in mesh can impose a performance penalty on some devices, so a partial mesh is implemented.

48. Physical topologies
he physical topology shows the actual physical layout of a network.
It may show buildings, rooms, the location of devices, cabling, data points, and wireless coverage.
WAN physical topologies show a map with the cable routes between centres.
Building floor plans can show the location of cables, data points, and wireless access points.
A physical topology is typically drawn to scale, and if not dimensioned, can be used, for example, to measure the size of rooms and the total length of cable used.
Installers use a physical topology to place equipment correctly in racks, and wire data points and wireless access points.
In an IoT environment, the physical topology shows the exact location of sensors and actuators.

49. Physical topologies
As previously stated, it is important to remember that the actual physical topology usually does not resemble the logical topology of that network.
Modern cabled networks are usually physically cabled back to a central point (a cross-connect, or patch, panel) to connect the devices to switch – that is, a physical star, or extended star, topology.
However, the actual logical topology (how the network operates) could be a bus, ring, or mesh type.

50. Physical topologies

51. Logical topologies

52. Activity Questions
Open Smart_City.pka file. Instructions for an activity will open with the file. Answer to the following questions:
What types of server are in the ISP-Cloud? (select 2)
Central Office (CO) server
ISP server
DNS-HTTP server
Coaxial server
2. Which two devices in the Smart Home are connected to the Cell Tower? (select 2)
Smart solar panel
Garage door
Tablet
Smart phone
Security alarm
Water meter

53. Activity Questions
3. What wireless connection point are all the other devices in the smart home connecting wirelessly to?
Modem
Tablet
Home gateway
Coaxial splitter
4. In Smart Parking, what two values are displayed for the P-Space-1 device on the City IT Laptop for when the space is free, and for when there is a car parked there?
0 & 20
1 & 2
O & U
V & T

54. Activity Questions
5. In Smart Traffic, what happens when you move the emergency vehicle towards the intersection?
The nearest traffic light goes green and the other goes red to stop counter traffic
Both traffic lights go red
Both traffic lights go green
The nearest traffic light goes red and the other traffic light goes green
6. What does the emergency vehicle wireless connect with?
Traffic modem
Traffic access point
City Office laptop
Traffic server

55. Activity Questions
7. In the Power Grid, what are the power sources connecting into the grid? (select 3)
Nuclear power station
Hydroelectric generator
Solar panels
Coal power station
Wind turbines
Tidal turbines
8. Reflect on the smart city topology generally. Which network protocol suite enables the smart city depicted to provide the complete range of communications shown?
Ethernet
Wi-Fi
TCP/IP
HTTP

56. Any Questions?