Understanding IoT Communication Protocols: 5G, NB-IoT, LoRa, ZigBee, NFC

(1) 2G/3G/4G Communication Protocols refer to the second, third, and fourth generations of mobile communication system protocols.

(2) NB-IoT

Narrow Band Internet of Things (NB-IoT) has become an important branch of the Internet of Everything. NB-IoT is built on cellular networks, consuming only about 180kHz of bandwidth, and can be directly deployed on GSM, UMTS, or LTE networks to reduce deployment costs and achieve smooth upgrades. NB-IoT focuses on the low-power wide-area (LPWA) IoT market and is an emerging technology that can be widely applied globally. It features wide coverage, many connections, fast rates, low costs, low power consumption, and excellent architecture.

Application scenarios: The scenarios brought by the NB-IoT network include smart parking, smart firefighting, smart water management, smart streetlights, shared bicycles, and smart home appliances.

(3) 5G

The fifth generation of mobile communication technology is the latest generation of cellular mobile communication technology. The performance goals of 5G include high data rates, reduced latency, energy savings, cost reduction, increased system capacity, and large-scale device connectivity.

Application scenarios: AR/VR, Internet of Vehicles, smart manufacturing, smart energy, wireless healthcare, wireless home entertainment, connected drones, ultra-high-definition/panoramic live streaming, personal AI assistance, smart cities.

(1) WiFi

Due to the rapid popularity of home WiFi routers and smartphones in recent years, the WiFi protocol has been widely used in the smart home field. The biggest advantage of the WiFi protocol is its ability to connect directly to the Internet. Compared to ZigBee, smart home solutions using WiFi protocol eliminate the need for additional gateways, and compared to Bluetooth protocol, they do not rely on mobile terminals such as smartphones.

Commercial WiFi coverage in urban public transportation, shopping malls, and other public places reveals the potential of commercial WiFi application scenarios.

(2) ZigBee

ZigBee is a low-speed, short-distance wireless communication protocol, characterized by high reliability, low speed, low power consumption, low cost, support for a large number of online nodes, support for various online topologies, low complexity, speed, reliability, and security.

ZigBee technology is a new technology that has recently emerged, primarily relying on wireless networks for transmission, enabling close-range wireless connections, and belonging to wireless network communication technology.

The inherent advantages of ZigBee technology have gradually made it a mainstream technology in the IoT industry, with large-scale applications in industrial, agricultural, and smart home fields.

(3) LoRa

LoRa™ (Long Range) is a modulation technology that provides longer communication distances compared to similar technologies. LoRa gateways, smoke detectors, water monitoring, infrared detection, positioning, and power strips are widely used IoT products. As a narrowband wireless technology, LoRa uses time of arrival differences to achieve geographic positioning. Application scenarios for LoRa positioning include smart cities and traffic monitoring, metering and logistics, and agricultural monitoring.

(1) RFID

Radio Frequency Identification (RFID) is the abbreviation for Radio Frequency Identification. Its principle is non-contact data communication between a reader and a tag to achieve the purpose of identifying the target. RFID has a wide range of applications, with typical applications including animal chips, automotive chip anti-theft devices, access control, parking management, production line automation, and material management. A complete RFID system consists of three parts: a reader, an electronic tag, and a data management system.

(2) NFC

NFC stands for Near Field Communication technology. NFC was developed based on non-contact RFID technology, combined with wireless interconnection technology, providing a very secure and convenient communication method for various electronic products that are becoming increasingly popular in our daily lives. The “near field” in the Chinese name of NFC refers to the electromagnetic field of radio waves in close proximity.

Application scenarios: Used in access control, attendance, visitor management, conference registration, patrol, etc. NFC has functions such as human-machine interaction and machine-to-machine interaction.

(3) Bluetooth

Bluetooth technology is a globally recognized standard for wireless data and voice communication, based on low-cost short-range wireless connections, establishing a communication environment for fixed and mobile devices.

Bluetooth enables wireless information exchange between numerous devices, including mobile phones, PDAs, wireless headsets, laptops, and related peripherals. Using Bluetooth technology can effectively simplify communication between mobile communication terminal devices and successfully streamline communication between devices and the Internet, making data transmission faster and more efficient, thus broadening the path for wireless communication.

(1) USB

USB is the abbreviation for Universal Serial Bus, an external bus standard used to specify the connection and communication between computers and external devices. It is an interface technology applied in the PC field.

(2) Serial Communication Protocol

The serial communication protocol specifies the content of data packets, which includes the start bit, main data, check bit, and stop bit. Both parties need to agree on a consistent data packet format to send and receive data normally. Common protocols in serial communication include RS-232, RS-422, and RS-485.

Serial communication refers to a way of transmitting data between peripherals and computers, bit by bit, through data lines. This communication method uses fewer data lines and can save communication costs in long-distance communication, but its transmission speed is lower than parallel transmission. Most computers (excluding laptops) contain two RS-232 serial ports. Serial communication is also a commonly used communication protocol for instruments and equipment.

(3) Ethernet

Ethernet is a computer local area network technology. The IEEE organization established the IEEE 802.3 standard, which sets the technical standards for Ethernet, including the physical layer wiring, electronic signals, and media access layer protocols.

(4) MBus

The MBus remote meter reading system is a European standard two-wire bus, primarily used for measuring instruments such as heat meters and water meters.

The Internet Protocol version 4 is the fourth revision in the development process of the Internet Protocol and is the first version of this protocol to be widely deployed. IPv4 is the core of the Internet and the most widely used version of the Internet protocol.

The Internet Protocol version 6 was developed to address the main issue of IPv4, which is the limited number of network address resources, severely restricting the application and development of the Internet. The use of IPv6 not only solves the problem of the number of network address resources but also addresses the barriers to connecting various access devices to the Internet.

The Transmission Control Protocol (TCP) is a connection-oriented, reliable, byte-stream-based transport layer communication protocol. TCP is designed to adapt to the layered protocol hierarchy that supports multiple network applications. It provides reliable communication services between paired processes in main computers connected to different but interlinked computer communication networks. TCP assumes it can obtain simple, possibly unreliable datagram service from lower-level protocols.

6LoWPAN is a low-power wireless personal area network standard based on IPv6, or IPv6 over IEEE 802.15.4.

MQTT (Message Queue Telemetry Transport) is a telemetry transport protocol that provides two messaging modes: subscribe/publish, which is simpler, lightweight, and easy to use, especially suitable for message distribution in constrained environments (low bandwidth, high network latency, unstable network communication), and is a standard transport protocol for the Internet of Things (IoT).

In many cases, including constrained environments, such as machine-to-machine (M2M) communication and the Internet of Things (IoT), it has been widely used in satellite link communication sensors, occasionally dial-up medical devices, smart homes, and some miniaturized devices.

CoAP (Constrained Application Protocol) is a web-like protocol in the IoT world, suitable for small low-power sensors, switches, valves, and similar components that require remote control or monitoring through standard Internet networks, with servers not responding to unsupported types.

RESTful is a software architectural style based on resources. A resource is an entity on the network or specific information on the network. An image or a song is a resource. RESTful API is an implementation based on the HTTP protocol. (HTTP is an application layer protocol characterized by simplicity and speed).

Applications or designs that meet the REST specification are RESTful, and APIs designed according to the REST specification are called RESTful APIs.

DDS (Data Distribution Service) is a middleware protocol for distributed real-time data distribution service, serving as the “TCP/IP” in real-time networks, used to solve interconnection of network protocols in real-time networks, functioning like “the bus on the bus”.

AMQP, or Advanced Message Queuing Protocol, is an application layer standard for unified messaging services, an open standard for application layer protocols designed for message-oriented middleware. Clients based on this protocol can transmit messages to message middleware without being restricted by different products, different programming languages, etc. Implementations in Erlang include RabbitMQ and others.

XMPP is a protocol based on a subset of standard generalized markup language XML, inheriting flexible development in the XML environment. Therefore, applications based on XMPP have strong scalability. After being extended, XMPP can handle user needs by sending extended information and establish applications such as content publishing systems and address-based services on top of XMPP.

First, Frequency Bands. LoRa operates in unlicensed frequency bands below 1GHz, requiring no additional payment for use. NB-IoT and cellular communication use licensed frequency bands below 1GHz, which require payment.

Second, Battery Life.LoRa modules have unique characteristics in dealing with interference, network overlap, scalability, etc., but cannot provide the same quality of service as cellular protocols. Due to considerations of service quality, NB-IoT cannot provide battery life similar to LoRa.

Third, Device Cost.For terminal nodes, the LoRa protocol is simpler, easier to develop, and has better applicability and compatibility with microprocessors than NB-IoT. Additionally, low-cost, relatively mature LoRa modules have already been found on the market, with upgraded versions coming out continuously.

Fourth, Network Coverage and Deployment Timeline.The NB-IoT standard was announced in 2016. In addition to network deployment, the corresponding commercialization and establishment of the industrial chain will require more time and effort to explore. The entire industrial chain of LoRa is relatively mature, and products are in a state of “ready to go,” while many countries worldwide are conducting or have completed nationwide network deployments.

Currently, WiFi’s advantages are its widespread application, having become common in thousands of households; ZigBee’s advantages are low power consumption and self-organization; UWB’s advantages are transmission rates; and Bluetooth’s advantage is its simple networking. However, these three technologies all have their shortcomings, and no single technology can fully meet all the requirements of smart homes.

The emergence of Bluetooth technology has made short-range wireless communication possible, but its complex protocol, high power consumption, and high cost characteristics are not suitable for industrial control and home networks that require low cost and low power consumption. Especially, Bluetooth’s biggest obstacle is its limited transmission range, usually around 10 meters, with weak anti-interference capability and information security issues being the main factors restricting its further development and large-scale application.

WiFi is also a short-range wireless transmission technology that can connect to wireless signals at any time, with strong mobility, making it suitable for use in office and home environments. Of course, WiFi also has a fatal flaw. Since WiFi uses radio frequency technology to send and receive data through the air, it is more susceptible to external interference.

ZigBee is an internationally recognized wireless communication technology, with each network port capable of connecting up to 65,000 ports, suitable for use in homes, industries, agriculture, and other fields, while Bluetooth and WiFi can only connect 10 ports, which obviously cannot meet the needs of households. ZigBee also has advantages in low power consumption and low cost.

MQTT is a many-to-many communication protocol used to transmit messages between different clients via an intermediate broker, decoupling producers and consumers by allowing clients to publish while the broker decides routing and copies messages. Although MQTT supports some persistence, it is best used as a real-time data communication bus.

CoAP is primarily a point-to-point protocol used to transmit status information between clients and servers. Although it supports observing resources, CoAP is best suited for state transfer models, not entirely event-based.

MQTT clients establish long TCP connections, which usually indicates no issues, while CoAP clients and servers send and receive UDP packets. In NAT environments, tunneling or port forwarding can be used to allow CoAP, or like LWM2M, devices may first initialize the front-end connection.

MQTT does not provide support for message type tagging or other metadata to help clients understand. MQTT messages can be used for any purpose, but all clients must know the upward data format to allow communication. CoAP, on the other hand, provides built-in support for content negotiation and discovery, allowing devices to probe each other to find ways to exchange data.

Both protocols have their advantages and disadvantages, and the choice depends on one’s application.

Source: Software New Perspective