In many communication systems, broadcasting can be realized by flooding without the information of network topology. In ad-hoc wireless networks where the network topology frequently changes, it is almost impossible to get the exact information of the network topology. Therefore, the flooding is a good candidate for broadcasting in ad-hoc wireless networks. However, the network bandwidth required for the flooding is sometimes too large for the bandwidth of ad-hoc wireless networks, since the flooding process generates scarce many packets in a short time. In this paper we propose two flooding algorithms to reduce the network bandwidth : donut flooding and selective flooding. Both of them prohibits the retransmission of packets, and efficiently utilize network bandwidth requirement. Simulation shows that the donut flooding can reduce network bandwidth.
