Comparison of advantages and disadvantages of three common wireless communication technologies connected to the Internet of Things

Among the short-range wireless communication technologies for implementing the Internet of Things, Bluetooth, Wi-Fi, and zigbee are the three most widely used short-range wireless communication technologies. What are the advantages and disadvantages of these three IoT communication technologies?

Bluetooth:
 Bluetooth (BlueTooth) is a technology for wireless communication between devices, which can realize short-distance data exchange between fixed devices, mobile devices and building personal area network. Bluetooth can connect multiple devices, overcoming the problem of data synchronization. Bluetooth uses short-baud high-frequency (UHF) radio waves to communicate via the ISM band from 2.4 to 2.485 GHz, with communication distances ranging from a few meters to several hundred meters.
Advantages:
Low power consumption in the "Bluetooth Low Energy" mode, with enhanced coverage and a maximum range of more than 100 meters
 Support for complex networks: optimized for one-to-one connections, and one-to-many connections in star topology, etc.
 Intelligent connection: Added support for setting the connection frequency between devices, IPv6 network support.
 Higher security: use AES-128 CCM encryption algorithm for data packet encryption and authentication.
 The Bluetooth module is small and easy to integrate.
 Ad-hoc Connection can be established temporarily: According to the role of the Bluetooth device in the network, it can be divided into a master device and a slave device.
Disadvantages:
 Various versions of Bluetooth are incompatible and have poor networking capabilities; there are few network nodes and it is not suitable for multi-point deployment.

Wi-Fi:
Wi-Fi is a wireless local area network communication technology, the full name is Wireless-Fidelity, wireless fidelity, the IEEE 802.11 standard of the IEEE organization has formulated the technical standard of Ethernet. Wi-Fi terminal refers to the use of high-frequency radio signals to send and receive data, using the Ethernet communication protocol, and the communication distance is usually tens of meters.
advantage
The advantage of Wi-Fi is that no wires are needed for LAN deployment, reducing the cost of deployment and expansion. In addition, according to the Wi-Fi Alliance designation, "Wi-Fi certification" is backward compatible and it specifies a set of globally unified standards: Unlike mobile phones, any Wi-Fi standard device will operate correctly anywhere in the world.
Disadvantage
The disadvantages of Wi-Fi are limited communication distance, poor stability, large power consumption, poor networking capability, and poor security.

ZigBee:
 It is a low-speed, low-power, short-range, self-organizing network wireless LAN communication technology. It was formally proposed in 2003. In order to compensate for the high complexity of the Bluetooth communication protocol, large power consumption, close distance, and small network size, etc. . The name is taken from the bees. The bees rely on the "dance" of flying and "zig" to shake their wings to communicate the location information of the pollen with their peers, and rely on this method to form a communication network in the group. ZigBee is standardized as IEEE 802.15.4, and has three working frequency bands: 868MHz-868.6MHz, 902MHz-928MHz, and 2.4GHz-2.4835GHz. The last frequency band is universal in the world, with 16 channels. Requested radio frequency band. The three bands have transmission rates of 20kbps, 40kbps, and 250kbps.
advantage:
 Low power consumption, large network capacity, flexible working frequency band.
Disadvantage
 The data transmission rate is low, the effective range is small, the anti-interference is poor, the ZigBee protocol is not open source, and the connection with the IP protocol is more complicated.