This paper has deeply studied the vulnerability of the BGP protocol running in the backbone routers, laid special stress on analysing the CXPST Attacks algorithm, and introduced the improved shock path selection strategies, theoretically proved that the improved shock path selected strategy better. Experimental tests show that the BGP protocol attacked with the designed algorithm is more effective than that of CXPST algorithm, which can result in the backbone routers running with BGP dropping down in less time.