MiWi protocol, a network protocol suitable for small IoT

There are many ways to achieve short-distance communication in our daily life, such as Bluetooth, WiFI, etc. However, in the Internet of Things, when a large number of electronic devices need to communicate at a low rate, it is not difficult to think of using the ZigBee protocol to achieve industrial automation, smart home, IoT security, etc. However, for college students, developers who are new to the Internet of Things, or even small smart home developers, this is still a bit difficult. Below I will introduce a small protocol that can quickly allow developers to form a lower power consumption and more convenient network - MiWi protocol network.

First, let me introduce the IEEE 802.15.4 standard. Many people may not know what it is, but everyone must have used WIFI and WLAN, which are based on the wireless LAN standard IEEE 802.11. To put it simply, this is the international organization's requirement that all WIFI and WLAN in the world must follow this standard. In addition to IEEE 802.11, there is also IEEE 802.15, and this working group is working on network standards for personal areas such as Bluetooth. The fourth task group is working on standards for low-speed wireless personal networks.

Those who have an impression of this should be able to remember that ZigBee is based on the IEEE 802.15.4 standard. WirelessHART and MiWi protocols are also based on this standard.

Of course, we use different network protocols for different network requirements. Students like me who have just entered the stage of learning the Internet of Things can use MiWi to practice.

Figure 1 Comparison of propagation distance and speed

Of course, it makes sense to say that it is simpler than other network protocols. Students who have studied network principles should know the OSI network protocol model.

Figure 2 Comparison between OSI model and MiWi protocol

In contrast, the MiWi protocol does not have a series of protocols between the application layer and the network layer because this small personal network does not have various external applications and does not need something like an interface to guide data packets. The composition of this protocol has already determined that its complexity will not be too high.

Although it and ZigBee are both based on the IEEE 802.15.4 standard, it cannot replace ZigBee, it can only be an alternative protocol for ZigBee.

• The characteristics of the MiWi protocol are:
• Mesh Network
• Peer-to-Peer (P2P)
• IEEE Address Search
• Sockets

The mesh network feature allows the MiWi protocol to search for multiple paths to the target node, which is similar to the ZigBee network. When the node to be connected is out of the signal range, the coordinator is used as a bridge to forward to the node to be connected, which meets the need to connect the virtual network in the fastest way. This protocol also allows IEEE access devices that do not comply with this network to be forced to exit.

Figure 3 Mesh network

The most important thing in this network is the PAN coordinator, which can be understood as the central brain. A maximum of 8 are allowed in the same network, and the sub-coordinator can accommodate 127. This is why this protocol cannot replace the ZigBee protocol.

Figure 4 MiWi protocol short address structure

Compared with ZigBee, MiWi has its own advantages, but also has its own disadvantages. Therefore, it is very important to use the appropriate network protocol for the appropriate scenario.

Figure 5 Comparison between MiWi protocol and ZigBee protocol