https://en.wikipedia.org/wiki/IEEE_802 http://www.ktword.co.kr/test/view/view.php?m_temp1=2303&id=372 컴퓨터 네트워킹, K-mooc, 유영환 https://lms.kmooc.kr/course/view.php?id=4969#section-12 https://naon.me/posts/til83
https://en.wikipedia.org/wiki/IEEE_802 http://www.ktword.co.kr/test/view/view.php?m_temp1=2303&id=372 컴퓨터 네트워킹, K-mooc, 유영환 https://lms.kmooc.kr/course/view.php?id=4969#section-12 https://naon.me/posts/til83