https://www.syu.ac.kr/blog/net-%ec%b1%8c%eb%a6%b0%ec%a7%80-%ec%8b%9c%ec%a6%8c8-i-ct-%ec%95%84%ec%9d%b4%eb%94%94%ec%96%b4-%ea%b2%bd%ec%a7%84%eb%8c%80%ed%9a%8c/net-%ec%b1%8c%eb%a6%b0%ec%a7%80-%ec%ba%a0%ed%94%84-%ec%8b%9c%ec%a6%8c8-%ec%95%88%eb%82%b4%ec%9e%90%eb%a3%8c/