Edge Networking

5Ad hoc and Mesh Networks

Mobile Ad hoc Networks or MANET are an important category of relay networks. The infrastructure consists only of the stations themselves, which act as a transmitter, receiver and router. Routing allows information to pass from one terminal to another without these terminals being directly connected. Mesh networks, as we saw in the previous chapter, require that the nodes be independent of the user’s machines.

5.1. Ad hoc networks

An ad hoc network is shown in Figure 5.1.

Contrary to appearances, ad hoc networks date back several decades. They aim to achieve a communication environment that is deployed without any other infrastructure than the mobiles themselves. In other words, mobiles can act as a gateway to enable communication from one mobile to another. Two mobiles that are too far apart to communicate directly can find an intermediate mobile that can act as a relay.

The major difficulty generated by this type of network comes from the very definition of the network topology: how to determine which nodes are neighbors and how to get from one node to another? Two extreme solutions can be compared. The first is that of an ad hoc network in which all nodes can communicate with all others, implying a long range of transmitters. In the second solution, on the other hand, the radio range is as short as possible: in order to communicate between two nodes, it is usually necessary to pass through several intermediate machines. The advantage of the first ...