An attack by knife-wielding men at a railway station in Kunming in south-west China has left at least 29 dead,and over 140 persons injured. After Kunming tragedy,all security updated in China area, Shanghai, Beijing, Guangzhou etc. big cities increased security guards to insure the safty.Most of us don't know what happened in Kunming station, but with our CCTV security surveillance, we know all situations inside and outside. Our CCTV lens, megapixel lens,are used there that we won't lost most of affairs. See below .