Flooding

Flooding can be used for routing wireless sensor networks. In flooding, a node sends a packet received, to all its neighbors other than the neighbor which sent the packet to it, if the packet is not destined to itself or the maximum number of hops a packet can pass is not crossed. Flooding is very simple to implement, and it is reactive protocol, as it does not maintain any routing table (topology maintenance) and does not require discovering any routes. But this technique has several disadvantages, the most important being, it is responsible for large bandwidth consumption and it wastes valuable energy. This is not an energy aware protocol also. This protocol is not designed specifically for sensor networks. Similar data produced by nodes in the same region are also flooded, i.e. there is no data aggregation done. The diagram below gives an example for flooding.



Flooding in WSN

Node 2 sends a packet to node 1, which in turn sends the packet to all its neighbors, i.e. to node 3, node 4, and node 5. Node 1 does not send the packet to node 1 because node 1 knows that node 2 only sent the data to it.