In the last tutorial, we have seen introduction to IoT. In this tutorial, I will talk about IoT protocols and their types. If we look closely at the term “Internet of Things”, it has two main words, Things and the Internet. Firstly, for the term “Internet” the first thing that comes up in our mind is a network that is used for global communication and thus enabling information sharing across the globe turning this planet into a global village. On the other hand, the other word “Things” we can refer to numerous IoT (internet of things) devices which are capable of performing actuating, remote sensing and live to monitor of different types of data. Additionally, all these IoT devices have unique identities so that they can be accessed over thousands of devices for the purpose of communication or any other.
A huge number of connected devices making the Internet of things (IoT) are expanding continuously over the globe. Now a number of devices around us are capable to process, collect and send data over servers or other connected devices. These devices are also used in many other ways like manufacturing, automotive, medicine, security system and much more. Therefore, let’s talk about IoT protocols and types of IoT protocols
INTRODUCTION to IoT protocols
The IoT system can perform and transfer information only when they are in online mode. For example, when devices in IoT are safely connected to communication networks. Here the question arises that how much connection is possible and what sort of connections are available for making these thousands of devices to communicate with each other. The answer to these entire questions is PROTOCOL. We can say that protocols enable these devices to communicate with each other and many protocols have been introduced so far and continuously many protocols are being introduced. Therefore, in this article are to going to discuss IoT network requirements, different types of protocols used in IoT. In the end, we provide a brief description of commonly used protocols in the Internet of Things.
IOT NETWORKS REQUIREMENTS
Some mandatory requirements to build an IoT network are listed below:
- Scalable i.e. can connect a large number of devices
- Highly reliable
- Support data transmission in real time with minimized delays
- Protect data flows
- Capable of configuring applications
- Traffic management and monitoring at device level
- It should be cost effective so that large number of devices can be connected.
Types of IoT PROTOCOLS
Although, there exist a large number of IoT protocols are used in IoT. but here we will be discussing some widely used protocols in the Internet of Things which are listed below:
- MQTT (message queue telemetry transport)
- DDS (data distribution service)
- AMQP (advance message queuing protocol)
So let’s discuss these protocols in detail.
The first IOT protocol we are going to explain is MQTT (message queue telemetry transport). It is a lightweight protocol and used for sending data from sensors to middleware and applications. Additionallty, it works on top of TCP / IP in order for providing reliable delivery of data. Furthermore, it has three main components
Hence, the basic workflow of this protocol is that the publisher is responsible for generating and transmission of information to subscribers through a broker. The main function of a broker is to ensure security by checking authorization of subscribers and publishers. This protocol is preferred for IoT devices because it provides well-organized information routing function to cheap, small, low memory and power devices and also low bandwidth networks.
DDS stands for data distribution service. In IoT it is used for scalable, real-time and for machine – machine high performance. This protocol can be used in devices as well as in cloud. Mainly, it consists of two main layers:
- DCPS i.e. data centric publish subscriber. It is used for delivering information to the subscribers
- DLRL i.e. data local reconstruction layer. It is used for providing an interface to the functions of DCPS.
AMQP stands for advance message queuing protocol. If we consider OSI model of internet architecture then this protocol is used at application layer. The processing of this protocol consists of three main components following some set of rules.
- Exchange: to receive messages and putting them in queues
- Message queue: for storing messages unless and until they are safely processed by the client applications
- Binding: it defines the relationship of exchange and message queue i.e. first and second component.
It is also a very famous IOT protocol. Furthermore, it is commonly used short range communication technology and is used mostly in mobile devices and smart phones. Furthermore, it is mostly used in personal products. This technology is real foundation for IoT and was designed in order to minimize power consumption. It is flexible and scalable to almost all market inventions. A new important protocol to use in IoT is Bluetooth Smart or BLE (Bluetooth low energy). At last, Some important points related to this protocol
- Uses Bluetooth 4.2 standard
- Frequency is of about 2.4 GHz
- Range is from 50 – 150m in case of smart Bluetooth or Bluetooth low energy
- Data rate is of 1 Mbps for smart or low energy Bluetooth
Another protocol we are going to discuss is Zigbee 3.0. The universal language for IoT was created by Zigbee alliance known as Dotdot. This language enabled smart devices to work seamlessly and securely on any type of network by understanding each other. Zigbee 3.0 has following features
- It is a low power protocol
- Comes in the category of wireless protocol offering low data rates
- Mostly used in industrial settings
- Zigbee 3.0 is based on IEEE 802.15.4 standard
- Frequency is of about 2.4 GHz
- Range is from 10 – 100 m for Zigbee 3.0
- Data rate is about 250 kbps.
In LAN environments, the most used type of connectivity is Wi-Fi. It is the technology that is used in radio wireless networking of devices. Below are some features of this protocol
- Fast data transfer is offered by this protocol
- It can be used to process large amount of data
- It is based on IEEE 802.11 standard
- Frequencies are of about 2.4 GHz and 5 GHz bands
- Range is approximately 50 m.
- Data rate are about 150 – 200 Mbps and can offer up to maximum of 600 Mbps.
The base of every mobile phone network is cellular technology. It is also used in Internet of Things applications which are designed to perform over large distance. These applications take benefit from the cellular communication technology such as 2 G, 3 G, 4 G and now 5G is going to launch soon. Some features of this protocol are given below:
- This technology is capable for transferring large amount of data
- High power consumption
- This technology is most suitable for projects which send small amount of information so that power consumption is low.
- Standards used in 2 G are GSM / EDGE / GPRS
- Standards used in 3 G are UMTS / HSPA
- Standard used in 4 G is LTE
- Frequencies can lie about 900 / 1800 / 1900 / 2100 MHz
- For GSM range is about 35 km and for HSPA it is about 200 km
- Data rate for GPRS is 35 – 170 Kbps, for EDGE 120 – 384 Kbps, for UMTS 384 Kbps – 2 Mbps, for HSPA 600 Kbps – 10 Mbps and for LTE 3 – 10 Mbps
Long range wide area network (LoRaWAN) is a protocol which is used for wide area networks. It is designed in such a way that it supports a huge amount of networks having millions of low power devices. Some features of this protocol are listed below:
- It is based on LoRaWAN standard
- It can operate on various frequencies
- Range of this protocol is 2 – 5 km in urban areas and 15 km in suburban areas
- Data rates lie in the range of 0.3 – 50 Kbps
SOME OTHER IOT PROTOCOLS
Although above-metioned protocols are mostly used and famous. But these are also available.
- UDP: stands for user data gram protocol. In reference to OSI model we can link this protocol to transport layer and is an alternative to TCP but it is unreliable but provide fast transmission of data and is one of the oldest protocol
- QUIC: for supporting multiplexed connections between two hosts over user datagram gram protocol (UDP) and for providing security
- IPv6: used in packet switched network and provide end to end datagram transmission over multiple IP networks
- DLTS (datagram transport layer): used to provide communication privacy in datagram protocol
- Nano-IP: e. Nano internet protocol was designed to bring internet services to sensors and embedded systems
Comparison of IoT Protocols
In summary, this table provides a comparison of all protocols according to various aspects.