Multicasting in mobile ad-hoc networks: achieving high packet delivery ratios

Multicasting is intended for group-oriented computing. There are more and more applications where one-to-many or many-to-many dissemination is an essential task. The multicast service is critical in applications characterized by the close collaboration of teams. Many applications, such as audio/video distribution, can tolerate loss of data content, but many other applications cannot. In addition, even loss-tolerant applications will suffer a performance penalty: an audio stream may experience a short gap or lower fidelity in the presence of loss. This paper describes our experience with implementing a multicast routing protocol that delivers packets to all intended recipients with high probability. Due to a number of reasons, 100% packet delivery cannot be achieved, but packet delivery ratios in excess of 99% are possible in most cases.