说明：  本书CCNA应试必要的学习指南， 由Cisco技术知名权威编写。本书共 11章，内容涉及网际互联、互联网协议、IP子网划分和变长子网划分掩码（VLSM）、Cisco IOS简介、IP路由、增强的IGRP（EIGRP）和开放最短路径优先（OSPF）、第2层交换、虚拟LAN、安全、管理Cisco互联网络、网络地址 转换、无线网络技术、IPv6和广域网。
(Necessary book CCNA exam study guide written by the leading authorities on Cisco technology. Book has 11 chapters, covering internetworking, Internet Protocol, IP subnetting and variable length subnetting mask (VLSM), Cisco IOS Introduction, IP routing, Enhanced IGRP (EIGRP) and Open Shortest Path First (OSPF) , Layer 2 switching, virtual LAN, security, management, Cisco Internet, network address translation, wireless networking, IPv6 and wide area networks.)