Moreover, each mobile host must be able to act both as a network router and an endpoint, because limited transmission ranges necessitate forwarding packets over multiple hops. Existing multicast protocols fall short because node mobility causes conventional multicast trees to rapidly become outdated. Frequent state changes require constant updates, reducing the already limited bandwidth available for data, and possibly never converging to accurately portray the current topology. Instead, a stateless multicast protocol is proposed for the above scenario. This is based on flooding the network with packets of the multicast stream.
Adaptive flooding is introduced to enhance multicast reliability in the face of high mobility.
Katia Obraczka, Internet Engineering Task Force Meeting , March 1999.