# IoT Protocols

**IoT protocols can be grouped into two different categories:**\
**(i) IoT Network Protocols**\
**(ii) IoT Data Protocols**

## **IoT Network Protocols**

Many communication technologies are well known such as WiFi, Bluetooth(BLE), ZigBee and 2G/3G/4G cellular apart from them some more new emerging networking protocols such as Thread, LowraaWAN, sigfox, subGig...etc

### **BLE**&#x20;

Bluetooth low energy or Bluetooth smart is a short range communication protocol with PHY and MAC layer widely used for in-vehicle networking. Its low energy can reach ten times less thanthe classic Bluetooth while its latency can reach 15 times.\
**Standard: Bluetooth 4.2 core specification**\
**Frequency: 2.4GHz (ISM)**\
**Range: 50-150m (Smart/BLE)**\
**Data Rates: 1Mbps (Smart/BLE)**

### **6Lowpan**

&#x20;A key IP (Internet Protocol)-based technology is 6LowPAN (IPv6 Low-power wireless Personal Area Network).IPv6 is the successor to IPv4 and offers approximately 5 x 1028 addresses for every person in the world, enabling any embedded object or device in the world to have its own unique IP address and connect to the Internet.\
**Frequency: adapted and used over a variety of other networking media including Bluetooth Smart (2.4GHz) or ZigBee or low-power RF (sub-1GHz)** \
**Standard: RFC6282**

### **ZigBee**

&#x20;ZigBee PRO and ZigBee Remote Control (RF4CE), among other available ZigBee profiles,are based on the IEEE802.15.4 protocol, which is an industry-standard wireless networking technology operating at 2.4GHz targeting applications that require relatively infrequent data exchanges at low data-rates over a restricted area and within a 100m range such as in a home or building.\
**Standard: ZigBee 3.0 based on IEEE802.15.4**\
**Frequency: 2.4GHz**\
**Range: 10-100m**\
**Data Rates: 250kbps.**

### **LoRaWAN**

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.\
**Standard: LoRaWAN**\
**Frequency: Various**\
**Range: 2-5km (urban environment), 15km (suburban environment)**\
**Data Rates: 0.3-50 kbps.**

### Sigfox

An alternative wide-range technology is Sigfox, which in terms of range comes between WiFi and cellular.The idea for Sigfox is that for many M2M applications that run on a small battery and only require low levels of data transfer, then WiFi’s range is too short while cellular is too expensive and also consumes too much power.\
**Standard: Sigfox.**\
**Frequency: 900MHz.**\
**Range: 30-50km (rural environments), 3-10km (urban environments).**\
**Data Rates: 10-1000bps.**

### Thread

A very new IP-based IPv6 networking protocol aimed at the home automation environmentis Thread.IPv6 and 6LoWPAN, and offers a resilient IP-based solution for the IoT.Thread supports a mesh network using IEEE802.15.4 radio transceivers and is capable of handling up to 250 nodes with high levels of authentication and encryption. \
**Standard: Thread, based on IEEE802.15.4 and 6LowPAN**\
**Frequency: 2.4GHz (ISM)**

### Wifi

The most common WiFi standard used in homes and many businesses is 802.11n, which offersserious throughput in the range of hundreds of megabit per second, which is fine for file transfers, but may be too power-consuming for many IoT applications\
**Standard: Based on 802.11n (most common usage in homes today)**\
**Frequencies: 2.4GHz and 5GHz bands**\
**Range: Approximately 50m**\
**Data Rates: 600 Mbps maximum, but 150-200Mbps is more typical, depending on channel frequency used and number of antennas (latest 802.11-ac standard should offer 500Mbps to 1Gbps).**

### Cellular (2G/3G/4G/5G):

Any IoT application that requires operation over longer distances can take advantage of GSM/3G/4G cellular communication capabilities. \
**Standard: GSM/GPRS/EDGE (2G), UMTS/HSPA (3G), LTE (4G)**\
**Frequencies: 900/1800/1900/2100MHz**\
**Range: 35km max for GSM; 200km max for HSPA**\
**Data Rates : 35-170kps (GPRS), 120-384kbps (EDGE), 384Kbps-2Mbps (UMTS), 600kbps-10Mbps (HSPA), 3-10Mbps (LTE).**

### IoT over Cellular Networks – LTE Cat-M1 and LTE Cat-M2 (NB-IoT)

The Third Generation Partnership Project (3GPP) is a technical body that develops standards for cellular phone communications.Cat-M1 is a reduced bandwidth/data rate/power protocol which can be deployed on current cellular networks. Cat-M2 is even more reduced but isn’t compatible with current LTE networks and would require chunks of GSM bandwidth to be allocated to it.

## IoT Data Protocols

### MQTT

It follows a publish/subscribe architecture, where the system consists of three main components: publishers, subscribers, and a broker. From IoT point of view, publishers are basically the lightweight sensors that connect to the broker to send their data and go back to sleep whenever possible. Subscribers are applications that are interested in a certain topic, or sensory data, so they connect to brokers to be informed whenever new data are received. The brokers classify sensory data in topics and send them to subscribers interested in the topics.\
&#x20; \


![MQTT Protocol](https://2940024201-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LbvnQRGvCTc2Zmsi6BG%2F-LdsDyWydpMGwcplsLh4%2F-LdsFp7YkSPE9TJzaiSV%2Fmqtt.png?alt=media\&token=441fc542-7268-42a1-b7e5-0372fbd7b81f)

### CoAP

Web protocol used in M2M with constrained requirements\
i. Asynchronous message exchange\
ii. Low overhead and very simple to parse\
iii. URI and content-type support\
iv. Proxy and caching capabilities\
&#x20;&#x20;

![CoAP](https://2940024201-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LbvnQRGvCTc2Zmsi6BG%2F-LdsDyWydpMGwcplsLh4%2F-LdsGCt989qBu4PKe6Jp%2Fcoap.png?alt=media\&token=8c31e957-99fc-4aac-8add-e15dca2996b1)

### REST

Rest stands for (Representational state transfer). IoT protocol, is exploited to exchange data between applications and to integrate applications belonging to different domains.Moreover, it uses HTTP as based protocol. Rest uses client/server paradigm. Rest is widely used notonly in IoT ecosystem. &#x20;

![REST](https://2940024201-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LbvnQRGvCTc2Zmsi6BG%2F-LdsDyWydpMGwcplsLh4%2F-LdsGUp0EcHOxYUhFOau%2Frest.png?alt=media\&token=2e4e2510-0c74-4112-8637-012922a3416b)

### MODBUS

Modbus is an open serial communication protocol that has become a standard communications protocol in industry, and is now the most commonly available means of connecting industrial electronic devices. It is used widely by many manufacturers throughout many industries. Versions of the Modbus protocol exist for serial lines (Modbus RTU and Modbus ASCII) and for Ethernet (Modbus TCP) &#x20;

![](https://2940024201-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LbvnQRGvCTc2Zmsi6BG%2F-LdsDyWydpMGwcplsLh4%2F-LdsGcVAlURE7xC-tdgD%2Fmodbus.png?alt=media\&token=0d1bd9a1-7365-47b9-b370-a0e2e53b891b)
