網絡上有許多na的教程，水平不一，我也看過許多的不同視頻了，下面爲朋友們分享我認爲比較好的視頻，一共四十講，最後還有工程案例分析。http://down.51cto.com/data/496142 16
http://down.51cto.com/data/496049 40
http://down.51cto.com/data/496046 39
http://down.51cto.com/data/496044 36-38
http://down.51cto.com/data/496043 34-35
http://down.51cto.com/data/496041 32-33
http://down.51cto.com/data/496040 30-31
http://down.51cto.com/data/496039 28-29
http://down.51cto.com/data/496021 26-27
http://down.51cto.com/data/496016 24-25
http://down.51cto.com/data/496014 22-23
http://down.51cto.com/data/496009 20-21
http://down.51cto.com/data/496007 17-18-19
http://down.51cto.com/data/496002 14-15
http://down.51cto.com/data/496000 13
http://down.51cto.com/data/495999 11-12
http://down.51cto.com/data/495998 10
http://down.51cto.com/data/495995 8-9
http://down.51cto.com/data/495991 7
http://down.51cto.com/data/495987 5-6
http://down.51cto.com/data/495982 3-4
http://down.51cto.com/data/495979 2
http://down.51cto.com/data/495974 1
http://down.51cto.com/data/436836
思科網絡學院CCNA packet tracer 全部實驗練習