以太网交换机基础培训教材 - 图文

以太网交换机基础培训教材

Catalog 目 录

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以太网概述 ........................................................................................................................... 6 以太网的基础知识 ................................................................................................................. 6 2.1 MAC地址 ................................................................................................................................................................6 2.2 以太网帧的帧格式 ...............................................................................................................................................7

2.2.1 以太网Ⅱ...............................................................................................................................................8 2.2.2 带有802.2逻辑链路控制的IEEE 802.3.......................................................................................8 2.2.3 IEEE 802.3子网访问协议（以太网SNAP）.............................................................................8 2.2.4 Novell以太网.......................................................................................................................................9 2.3 CSMA/CD ..............................................................................................................................................................9 2.4 冲突域和广播域..................................................................................................................................................10 2.5 以太网的典型设备-HUB ..................................................................................................................................10 2.6 全双工以太网 ......................................................................................................................................................11 二层交换机的基本原理 ........................................................................................................ 11 3.1 二层交换机 ..........................................................................................................................................................11 3.2 支持VLAN的二层交换机 .................................................................................................................................14

3.2.1 VLAN的概念 .....................................................................................................................................15 3.2.2 VLAN的划分 .....................................................................................................................................16 3.2.3 VLAN的标准 .....................................................................................................................................17 3.2.4 支持VLAN交换机的转发流程 ......................................................................................................19 三层交换机基本原理 ........................................................................................................... 22 4.1 三层交换机的提出 .............................................................................................................................................22 4.2 三层交换机基本特征.........................................................................................................................................23 4.3 三层交换机的功能模型 ....................................................................................................................................23 4.4 三层交换机转发流程.........................................................................................................................................25

4.4.1 IP网络规则 ........................................................................................................................................25 4.4.2 三层转发流程....................................................................................................................................25 4.4.3 选路过程.............................................................................................................................................27 4.5 路由器和交换机..................................................................................................................................................29

4.5.1 接口 .....................................................................................................................................................30 4.5.2 特点对照.............................................................................................................................................30 交换机相关协议和技术 ........................................................................................................ 30 5.1 物理层特性（接口）.........................................................................................................................................30

5.1.1 自协商 .................................................................................................................................................31 5.1.2 智能MDI/MDIX自识别....................................................................................................................31 5.1.3 流控机制.............................................................................................................................................32 5.1.4 POE供电 ............................................................................................................................................33 5.1.5 端口镜像.............................................................................................................................................33 5.2 二层协议和特性..................................................................................................................................................33

5.2.1 STP/RSTP/MSTP协议 ..................................................................................................................34 5.2.2 GARP/GVRP/GMRP .....................................................................................................................35 5.2.3 聚合特性.............................................................................................................................................36 5.2.4 Isolate-user-vlan .............................................................................................................................37 5.2.5 二层多播.............................................................................................................................................38 5.2.6 QinQ ....................................................................................................................................................39 5.3 三层特性 ...............................................................................................................................................................39

5.3.1 SuperVLAN .......................................................................................................................................39

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以太网交换机基础培训教材

5.4 Qos/ACL...............................................................................................................................................................40 5.5 安全特性 ...............................................................................................................................................................40

5.5.1 802.1X ................................................................................................................................................40 5.5.2 PORTAL.............................................................................................................................................42 5.6 管理特性 ...............................................................................................................................................................43

5.6.1 集群管理.............................................................................................................................................44 5.6.2 WEB网管 ...........................................................................................................................................45 5.7 IRF..........................................................................................................................................................................45 5.8 与路由器相同的一些特性................................................................................................................................47

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以太网交换机主要厂商 ........................................................................................................ 47 6.1 Cisco......................................................................................................................................................................47 6.2 Extreme ................................................................................................................................................................48 6.3 Foundry ................................................................................................................................................................48 6.4 港湾........................................................................................................................................................................48 参考资料 ............................................................................................................................. 48

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以太网交换机基础培训教材

图索引

图 1 图 2 图 3 图 4 图 5 图 6 图 7 图 8 图 9 图 10 图 11 图 12 图 13 图 14 图 15 图 16 图 17 图 18 图 19 图 20 图 21 图 22 图 23 图 24 图 25 图 26 图 27 图 28 图 29 图 30 图 31 图 32 图 33 图 34 图 35 图 36

MAC地址.......................................................................................................................................................7 常用的以太网帧格式..................................................................................................................................8 由HUB组成的网络....................................................................................................................................11 全双工以太网 .............................................................................................................................................11 二层交换机结构示意图 ...........................................................................................................................12 二层交换机的转发流程 ...........................................................................................................................13 二层交换机工作在链路层.......................................................................................................................13 交换机的冲突域和广播域.......................................................................................................................14 由二层交换机构成的扁平网络 ..............................................................................................................14 基于端口VLAN的划分 ............................................................................................................................16 802.1Q VLAN帧格式................................................................................................................................18 Trunk链路实现虚拟工作组.....................................................................................................................18 支持VLAN交换机交换引擎 ...................................................................................................................19 IVL和SVL地址学习方式.........................................................................................................................20 IVL地址学习方式转发流程....................................................................................................................21 SVL地址学习方式转发流程...................................................................................................................21 支持VLAN交换机冲突域和广播域 ......................................................................................................22 三层交换机功能模型................................................................................................................................24 三层交换引擎 .............................................................................................................................................24 三层转发流程 .............................................................................................................................................26 路由器的最长匹配转发 ...........................................................................................................................28 三层交换机转发-精确匹配 .....................................................................................................................29 三层交换机转发-最长匹配 .....................................................................................................................29 以太网的自协商.........................................................................................................................................31 STP阻塞网络环路 .....................................................................................................................................34 MSTP根据VLAN进行阻塞链路 ............................................................................................................35 GARP属性注册和注销.............................................................................................................................35 GARP基本原理 ..........................................................................................................................................36 Isolate-user-vlan..........................................................................................................................................37 不支持多播功能交换机 ...........................................................................................................................38 QinQ实现vMAN ........................................................................................................................................39 802.1X认证体系结构................................................................................................................................41 PORTAL认证四大要素............................................................................................................................43 集群的组成 .................................................................................................................................................45 IRF的组成 ...................................................................................................................................................46 IRF的典型应用...........................................................................................................................................47

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以太网交换机基础培训教材

表索引

表 1. 表 2. 表 3.

LAN/MAN参考模型 .................................................................................................................................15 路由器和三层交换机的特点对比 .........................................................................................................30 PORTAL、PPPoE/A、802.1X三种认证方式的特点对比...............................................................43

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以太网交换机基础培训教材

以太网交换机基础培训教材

Keywords 关键词：以太网，交换机，LAN，VLAN，IRF

Abstract 摘 要：本文介绍以太网交换机的相关知识和基本原理。主要包括：1）以太网交换机基

础知识；2）二、三层交换机的基本原理和转发流程；3）以太网交换机常用特性和技术。

List of abbreviations 缩略语清单： Abbreviations 缩略语 POE IVL SVL VLAN GVRP RSTP MSTP LACP DHCP NTP VRRP RIP OSPF IS-IS Full spelling 英文全名 Chinese explanation 中文解释 以太网供电 独立vlan学习 共享vlan学习 虚拟局域网 通用vlan注册协议 快速生成树协议 多实例生成树协议 链路聚合控制协议 动态主机配置协议 网络时间协议 虚拟路由冗余协议 路由信息协议 开放最短路径优先 IS-IS路由协议 边界网关协议 Internet组管理协议 IGMP侦听 通用组播注册协议 密集模式协议无关组播 稀疏模式协议无关组播 组播源发现协议 加权随机早期检测 质询握手验证协议 密码验证协议 可扩展认证协议 安全外壳 入侵检测系统 远程监控 华为组管理协议 邻居发现协议 智能弹性架构 Power Over Ethernet Independent Vlan Learning Sharing Vlan Learning Virtual Local Area Network Generic Vlan Registration Protocol Rapid Spanning Tree Protocol Multiple Spanning Tree Protocol Link Aggregation Control Protocol Dynamic Host Configuration Protocol Network Time Protocol Virtual Router Redundancy Protocol Routing Information Protocol Open Shortest Path First Intermediate System-to-Intermediate System intra-domain routing information exchange protocol BGP Border Gateway Protocol IGMP Internet Group Management Protocol IGMP Snooping Internet Group Management Protocol Snooping GMRP Generic Multicast Registration Protocol PIM-DM Protocol Independent Multicast-Dense Mode PIM-SM Protocol Independent Multicast-Sparse Mode MSDP Multicast Source Discovery Protocol WRED Weighted Random Early Detection CHAP Challenge Handshake Authentication Protocol PAP Password Authentication Protocol EAP Extensible Authentication Protocol SSH Secure Shell IDS Intrusion Detection System RMON Remote MONitor HGMP Huawei Group Management Protocol NDP Neighbor Discovery Protocol IRF Intelligent Resilient Framework Page 5 , Total 48 第5页，共48页