A wireless mesh network (WMN) is a communications network that consists of multiple wirelessly connected APs in a mesh topology and connects to a wired network through a portal node or two portal nodes.
Purpose
On a traditional WLAN, APs exchange data with STAs using wireless channels and connect to a wired network through uplinks. If no wired network is available before a WLAN is constructed, it takes much time and money to construct a wired network. If positions of some APs on a WLAN are adjusted, the wired network must be adjusted accordingly, increasing the difficulty in network adjustment. A traditional WLAN requires a long construction period and has a high cost and poor flexibility, so it does not apply to emergency communication, wireless MANs, or areas that lack weak wired network infrastructure. The construction of a WMN requires only APs to be installed, which greatly speeds up network construction.
A WMN allows APs to wirelessly connect to each other, solving the preceding problems. A WMN has the following advantages:
Fast deployment: Mesh nodes can be easily installed to construct a WMN in a short time, much shorter than the construction period of a traditional WLAN.
Dynamic coverage area expansion: As more mesh nodes are deployed on a WMN, the WMN coverage area can be rapidly expanded.
Robustness: A WMN is a peer network that will not be affected by the failure of a single node. If a node fails, packets are forwarded to the destination node along the backup path.
Flexible networking: An AP can join or leave a WMN easily, allowing for flexible networking.
Various application scenarios: Besides traditional WLAN scenarios such as enterprise networks, office networks, and campus networks, a WMN also applies to scenarios such as large-scale warehouses, docks, MANs, metro lines, and emergency communications.
Cost-effectiveness: Only MPPs need to connect to a wired network, which minimizes the dependency of a WMN on wired devices and saves costs in wired device purchasing and cable deployment.
Benefits
A WMN saves cables required between mesh nodes while providing path redundancy and rerouting functions as a distributed network. Therefore,
When a new AP is added to a WMN, the AP can automatically connect to the WMN and determine the optimal multi-hop transmission path after being powered on.
When an AP is moved from a WMN, the WMN can automatically discover the topology change and adjust communication routes to obtain the optimal transmission path.

