Abstract
On a highway, it has high potential of ‘chain-reaction collision’ to occur, since vehicle has high velocity. As a preventive method for chain-reaction collision, native broadcasting and intelligent broadcasting that sends emergency messages to rear vehicles were proposed. However, these methods were ineffective when vehicles were concentrated in one area. This paper offers you a broadcasting method that considers stopping distance and improved back-off algorithm based on the number of neighbor nodes, which solves previous problems. As a result, the frame reception success rate comparing two different methods, broadcasting methods considering dangerous factors, was 7 % improved than native and intelligent broadcasting.