说明：  全国计算机等级考试中三级网络技术有许多知识点，如何更加合理的学习与考试，是一个重点，好的学习指导往往是成功的一半！
(There are many knowledge points about network technology in the national computer grade test. How to study and test more reasonably is a key point. Good learning guidance is often half of success!)