Network Technology Research Institute, China United Network Communications Corporation Limited, No.9, Shouti Nanlu, Haidian District, Beijing 100048, China;
Network and Information Security Research Department,Electronic Technology Information Research Institute, MIIT, No.35, Lugu Road, Shijingshan District, Beijing 100040, China;
Network Technology Research Institute, China United Network Communications Corporation Limited, No.9, Shouti Nanlu, Haidian District, Beijing 100048, China;
Tencent Research, Shanghai, China;
School of Electronic and Information Engineering,Beijing Jiaotong University, Beijing 100044, China;
