Improving the PIM routing protocol with adaptive switching mechanism between its two sparse sub-modes

We present an extension of the classical PIM (protocol independent multicast) routing protocol, named PIM SWITCH, that allows PIM to dynamically switch between its shared tree sub-mode and shortest-path tree sub-mode. This extension enables PIM to better adapt to the changing networking environment. PIM SWITCH has been extensively, evaluated using our software tool MCS (multicast simulation) reported in a previous paper. Our simulation results reveal that PIM SWITCH performs well as expected with minimum overhead.