. The congestion probability of using BEB algorithm is 0.9998 when the number of node is 17, the congestion probability of using the improved algorithm is 0.9975, the average congestion probability of BEB algorithm is 0.9979, the average congestion probability of the improved algorithm is 0.9963 in the whole process, it decreases the congestion probability obviously, the contrast results of congestion probability of the two algorithm as shown figure 4.