Method for route recovery in wireless network of tree topology

A route recovery method in a wireless network of a tree topology having a plurality of nodes, in which a second node, which is a lower node of a first node and is disconnected from the first node, recovers a route in the network, the route recovery method comprising:

• the second node broadcasting a local repair request (LREQ) packet;
• at least one of the nodes receiving the LREQ packet and sending a local repair reply (LREP) packet to the second node to act as a relay node for the route recovery;
• the second node selecting the relay node from among the nodes sending the LREP packet, and sending a local repair confirm (LCON) packet to the selected relay node;
• and
• establishing the route between the second node and the first node by the relay node sending a local repair inform (LINF) packet to the first node,
• wherein the wireless network is of a tree topology and the second node, which is the lower node of the first node and is disconnected from the first node, recovers the route in the network,
• wherein the route is established between a third node, which is an upper node of the first node, and the second node by sending the LINF packet to the third node when the first node is disconnected from the network, and
• wherein a fourth node, which is a lower node of the second node, re-broadcasts the LREQ packet when the second node does not receive the LREP packet for a predetermined amount of time.