Qhov Rooj Hluav Taws Kub Hlau

Qhov rooj hluav taws kub yog lub qhov rooj nrog kev tiv thaiv hluav taws kub (qee zaum hu ua kev tiv thaiv hluav taws kub Hauv North American Tsev Codes, nws yog feem ntau xa mus rau qhov cub hluav taws, uas tuaj yeem muab cov teeb meem no tsis yog firewall lossis kev sib cais.