A mesh topology is a type of network topology in which all devices are interconnected with each other, forming a mesh-like structure. In this topology, each device connects directly to multiple other devices, allowing for multiple paths between devices and enhancing redundancy and fault tolerance. Mesh networks can be wired or wireless, and they can relay messages using either a flooding or a routing technique.

There are two main types of mesh topologies: full mesh topology and partial mesh topology. In a full mesh topology, every device in the network has a connection to each of the other devices in that network, resulting in a high degree of redundancy. The number of connections in this network can be calculated using the formula n(n-1)/2, where n is the number of devices in the network. In a partially-connected mesh topology, at least two of the devices in the network have connections to multiple other devices in that network, which is an inexpensive way to implement redundancy in a network.

Mesh networks have several advantages, including robustness and fault tolerance, high scalability, and efficient data transmission. They can manage high amounts of traffic, and a failure of one device does not cause a break in the network or transmission of data. Adding additional devices does not disrupt data transmission between other devices. However, the cost to implement a mesh topology is higher than other network topologies.

Mesh topology is commonly used in wireless networks, such as wireless sensor networks and wireless mesh networks. It is also used in home monitoring, industrial monitoring and control, medical monitoring, and more.