最新CCNA课件1_静态路由-动态路由.ppt

1、课程内容,Introducing Routing,Medium-Sized Routed Network Construction,Outline,Routing Overview Static and Dynamic Route Comparison Static Route Configuration Default Route Forwarding Configuration Static Routing Configuration Verification Dynamic Routing Protocol Overview Features of Dynamic Routing Pro

2、tocols The ip classless Command Inter VLAN Routing Summary,A router needs to do the following: 识别目标地址； 识别数据来源； 识别去往目标网络可能的所有路由(路径)； 选择前往目标网络的最佳路由； 维护路由信息。,Router Operations,路由选择-是确定将本地网络外部的数据分组发送到外部的过程.,Router Operations (Cont.),路由-用于前往不与目标网络直接相连的网络,Identifying Static and Dynamic Routes,Static Route

3、s,Configure unidirectional static routes to and from a stub network to allow communications to occur.,Defines a path to an IP destination network or subnet or host Address = IP address of the next hop router Interface = outbound interface of the local router,RouterX(config)# ip route network mask ad

4、dress | interfacedistance permanent,Static Route Configuration,Static Route Example,This is a unidirectional route. You must have a route configured in the opposite direction.,RouterA(config)# ip route 172.16.1.0 255.255.255.0 172.16.2.1,RouterA(config)# ip route 172.16.1.0 255.255.255.0 s0/0/0,or,D

5、efault Routes,This route allows the stub network to reach all known networks beyond Router A.,Verifying the Static Route Configuration,RouterX# show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area E1 - O

6、SPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route Gateway of last resort is 0.0.0.0 to network 0.0.0.0 10.0.0.0/8 is subnetted, 1 subnets C 10.1.1.0 is directly connected, Serial0/0/0 S* 0.0.0.0/

7、0 is directly connected, Serial0,Static route LAB,Benefits and Drawbacks of Static Routing,Benefits of Static Routing ： conserve memory and CPU. conserve bandwidth. Be applicable Stub Network. Drawbacks of Static Routing ： Technician must know the whole networks topology. Administration and maintena

8、nce difficulty. Not suited for large network.,What Is a Dynamic Routing Protocol?,动态路由协议是被路由器 用来自动地在网络里学习 路由和维护路由表的,AS：被统一管理的一组网络（165535） IGP：用于在自主系统内部交换路由选择信息的路由选择协议 EGP：用于在自主系统之间交换路由选择信息的路由选择协议,Autonomous Systems: Interior and Exterior Routing Protocols,Classes of Routing Protocols,距离矢量,基于距离矢量的路由选

9、择算法在路由器之间定期(RIP为30秒更新一次,IGRP为90秒)地传递路由选择表,并累计距离矢量(举例意味着多远,矢量意味着沿什么方向).路由器之间定期传递的更新用于交流拓扑变化信息. 每台路由器在信息上都依赖于自己的相邻路由器，而它的相邻路由器又是通过自它们自己的相邻路由器那里学习路由，依此类推.所以我们一般把距离矢量路由协议称之为“依照传闻的路由协议”,链路状态,链路状态名称的由来是因为它通过向它的邻站发送链路状态报文，通知它所知道的所有链路信息的。 每台路由器通过发送链路状态通告（LSA）或者链路状态包（LSP）了解了整个网络拓扑结构，就好比是拥有一张地图。与通过邻居“传闻”来学习路由

10、的距离矢量路由协议是不一样的。,Selecting the Best Route Using Metrics,Administrative Distance: Ranking Routing Sources,Routers choose the routing source with the best administrative distance: OSPF has an administrative distance of 110. EIGRP has an administrative distance of 90.,Administrative Distance管理距离,管理距离是指一

11、种路由协议的路由可信度。每一种路由协议按可靠性从高到低，依次分配一个信任等级，这个信任等级就叫管理距离。对于两种不同的路由协议到一个目的地的路由信息，路由器首先根据管理距离决定相信哪一个协议。,Administrative Distance,Classful Routing Overview,有类路由选择协议：不传递子网信息的路由选择协议。 有类路由选择协议发送路由通告时不包含子网掩码。 有类路由选择协议会在边界路由器这里进行自动汇总。 These are examples of classful routing protocols: RIP version 1 (RIPv1) IGRP,Cl

12、assless Routing Overview,无类路由选择协议发送路由通告时包含子网掩码。 无类路由选择协议支持可变长子网掩码 (VLSM)。 无类路由选择协议可以通过手工汇总。 These are examples of classless routing protocols: RIP version 2 (RIPv2) EIGRP OSPF IS-IS,有类路由选择协议路由方式,无类路由选择协议路由方式,Using the ip classless Command,Routing Protocol Comparison Chart,VLAN-to-VLAN Overview,Network layer devices