A node device in a tree-type broadcast system having hierarchy levels of node devices while locating a broadcast device at its top, whereby information is sequentially transferred from a higher hierarchy level to a lower hierarchy level, the node device including:
a means for receiving connection destination candidate information, broadcasted from the node device in the higher hierarchy currently connected or from the broadcast device;
a means for specifying a node device suitable as a reconnection destination candidate out of the connection destination candidate information;
a means for memorizing network address information, being the reconnection destination candidate; and
a means for selecting one node device memorized in the reconnection destination candidate memory means as the reconnection destination and connecting to it when the connection to the node device or the broadcast device is released and the own node device is newly reconnected to another node device.