For the watermark information construction is relative to the vertex location and can be used as the key to detect the watermark. Only the one who owns the correct key can detect the watermark information, which ensures the security of the algorithm. 水印信息序列的嵌入与顶点的位置有关,可以作为水印的检测密钥来使用,只有拥有正确的密钥才能抽取水印序列,使水印嵌入算法的安全性得到加强。