All networks, whether wired or wireless, have some kind of topology, defined as the network's shape or structure. A wired network's topology is physical and conforms to the layout of cabling in the network. Wireless network topology, on the other hand, is a logical topology conforming to the way the member computers connect and interact with each other, as there is no cable connecting the computers.
Wireless Network Topologies.
In a wireless network, all participating computers potentially communicate with each other directly. Wireless networks therefore have only two topologies: infrastructure and ad hoc. This is a direct and natural result of the non-physical nature of interaction of computers in a wireless network.
Infrastructure Network Topology
The infrastructure wireless network topology is a hub and spoke topology, also known as a point to multipoint or one to many topology. In the infrastructure topology, there is a single central wireless access point (WAP). The WAP acts as the hub in the network, with all the other computers (or spokes) connecting to it.
Ad Hoc Network Topology
An ad hoc wireless network topology is a many to many (or multipoint to multipoint) topology. There is no central access point in an ad hoc network structure; every computer in the network communicates directly with every other computer in the network. Ad hoc wireless network topologies are essentially mesh networks.
Advantages and Disadvantages of Wireless Network Topologies
The ad hoc topology has the advantage of not requiring a central access point or WAP. However, this also means that only a few security modes and much lower network speeds are available on such networks. Typically, only wired equivalent privacy (WEP) and a maximum speed of 11 megabits per second are implemented on ad hoc networks. Infrastructure networks, on the other hand, require the extra equipment of a central WAP. However, this brings the advantage of higher speeds and stronger security to such networks.
Wireless networks fall into only two types of network topologies: infrastructure and ad hoc. Each of these typologies has its own advantages and disadvantages and is suitable for different usage situations. The infrastructure topology is typically used for permanent networks, while the ad hoc topology is used for temporary networks.