To improve the performance of flooding

an efficient broadcasting algorithm with constrained flooding was proposed

this algorithm only selected efficient some from all routing packets to forward according to Euclidean Distance.A packet listening method

which could reduce route maintenance overhead and route discovery frequency

was studied

then a local route repair and optimization algorithm

which was based on node height and can repair the failure path due to link breakage

was presented.Furthermore

based on the efficient broadcasting algorithm and local route repair and optimization algorithm

a new on-demand routing protocol

named LOOR（low overhead on-demand routing）

was proposed.The simulation results on ns2 show that LOOR can enhance the route robustness

decrease the average hop count

the route discovery frequency and the routing overhead obviously

and increase the packet delivery ratio.