本书是神州数码DCNP（神州数码认证网络工程师）认证考试的指定教材。本书主要内容包括交换网络的技术实现、园区网实现VLAN、园区网实现冗余链路、多层交换机的路由实现、多层交换设备实现、园区网高可用性、园区网服务质量和IP组播。
本书可作为各类职业院校计算机应用技术和计算机网络技术专业的教材，也可作为交换机和网络维护的指导书，还可作为计算机网络工程技术岗位培训的参考用书。
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目 录
前言
二维码索引
第1章 交换网络的技术实现 ...................................................................................................1
1.1　传统以太网 ...........................................................................................................................1
1.2　交换网络的现状 ...................................................................................................................5
1.3　交换网络的发展趋势 ...........................................................................................................9
1.4　交换网络设计分层模型 .....................................................................................................10
1.5　交换网络设计分层实例 .....................................................................................................11
1.6　本章小结 .............................................................................................................................19
1.7　习题 .....................................................................................................................................19
第2章 园区网实现VLAN...........................................................................................................20
2.1　VLAN技术 ..........................................................................................................................20
2.2　VLAN技术及其应用 ..........................................................................................................22
2.3　端口MAC绑定 ....................................................................................................................25
2.4　本章小结 .............................................................................................................................26
2.5　习题 .....................................................................................................................................26
第3章 园区网实现冗余链路 .................................................................................................27
3.1　生成树协议的演化 .............................................................................................................27
3.2　快速生成树协议 .................................................................................................................32
3.3　多生成树协议 .....................................................................................................................40
3.4　生成树的保护机制 .............................................................................................................43
3.5　避免转发环路和黑洞 .........................................................................................................43
3.6　链路聚合 .............................................................................................................................45
3.7　本章小结 .............................................................................................................................48
3.8　习题 .....................................................................................................................................49
第4章 多层交换机的路由实现 .............................................................................................50
4.1　多层交换机功能概述 .........................................................................................................50
4.2　多层交换设备的直连网络 .................................................................................................50
4.3　多层交换设备的静态路由 .................................................................................................52
4.4　多层交换设备的动态路由 .................................................................................................56
4.5　VLAN间路由 ......................................................................................................................60
4.6　本章小结 .............................................................................................................................63
4.7　习题 .....................................................................................................................................63
第5章 多层交换设备实现.......................................................................................................64
5.1　多层交换设备的分类 .........................................................................................................64
5.2　二层交换设备的交换原理 .................................................................................................64
5.3　多层交换设备的交换原理 .................................................................................................69
5.4　本章小结 .............................................................................................................................82
5.5　习题 .....................................................................................................................................82
第6章 园区网高可用性...........................................................................................................84
6.1　虚拟路由的应用 .................................................................................................................84
6.2　虚拟冗余路由协议（VRRP） ...........................................................................................86
6.3　热备份路由协议（HSRP） ...............................................................................................90
6.4　Syslog ..................................................................................................................................92
6.5　简单网络管理协议（SNMP） ..........................................................................................93
6.6　本章小结 .............................................................................................................................94
6.7　习题 .....................................................................................................................................94
第7章 园区网服务质量...........................................................................................................96
7.1　园区网QoS概述 ..................................................................................................................96
7.2　交换机中的QoS实现 ........................................................................................................103
7.3　QoS配置 ............................................................................................................................107
7.4　本章小结 ............................................................................................................................111
7.5　习题 ...................................................................................................................................112
第8章 IP组播............................................................................................................................113
8.1　IP组播简介 ........................................................................................................................113
8.2　组播成员协议 ...................................................................................................................117
8.3　组播路由选择协议 ...........................................................................................................123
8.4　组播配置 ...........................................................................................................................130
8.5　本章小结 ...........................................................................................................................131
8.6　习题 ...................................................................................................................................131
习题答案......................................................................................................................................134
参考文献......................................................................................................................................135