路由routing的概念講課教案

1、路由routing的概念路由表和目的地址缺省網(wǎng)關(guān)（default gateway）（可）被路由的協(xié)議和路由協(xié)議缺省網(wǎng)關(guān)（default gateway）有類(lèi)和無(wú)類(lèi)路由協(xié)議有類(lèi)路由協(xié)議無(wú)類(lèi)路由協(xié)議和VLSM無(wú)類(lèi)域間路由選擇CIDR路由匯總（route summarization）路由表查找的例子路由器路由器S1: 194.24.0.0/21Packet: DestinationIP address: 194.24.17.4S2: 194.24.16.0/20S3: 194.24.8.0/22S1: 8CS3: 4CS2: 16C路由表查找：最長(zhǎng)匹配R2R3R1R4All 10/8 except1

2、0.1/16Packet: DestinationIP address: 10.1.1.110/8 - R310.1/16 - R420/8 - R530/8 - R6.R2s IP routing table10.1/16路由表查找：最長(zhǎng)匹配R2R3R1R4All 10/8 except10.1/1610.1/1610/8 - R310.1/16 - R420/8 - R5.R2s IP routing table10.1.1.1 & FF.0.0.0 is equal to10.0.0.0 & FF.0.0.0Match!Packet: DestinationIP address: 10.

3、1.1.1路由表查找：最長(zhǎng)匹配R2R3R1R4All 10/8 except10.1/1610/8 - R310.1/16 - R420/8 - R5.R2s IP routing table10.1.1.1 & FF.FF.0.0 is equal to10.1.0.0 & FF.FF.0.0Match as well!Packet: DestinationIP address: 10.1.1.110.1/16路由表查找：最長(zhǎng)匹配R2R3R1R4All 10/8 except10.1/1610/8 - R310.1/16 - R420/8 - R5.R2s IP routing table1

4、0.1.1.1 & FF.0.0.0 isnt equal to20.0.0.0 & FF.0.0.0Does not match!Packet: DestinationIP address: 10.1.1.110.1/16路由表查找：最長(zhǎng)匹配R2R3R1R4All 10/8 except10.1/1610/8 - R310.1/16 - R420/8 - R5.R2s IP routing tableLongest match, 16 bit netmaskPacket: DestinationIP address: 10.1.1.110.1/16Internet上的兩類(lèi)路由協(xié)議路由信息協(xié)議

5、RIPRIP的報(bào)文格式1：請(qǐng)求2：響應(yīng)RIP的操作模式RIP工作原理示意無(wú)窮計(jì)算(count-to-infinity)的問(wèn)題無(wú)窮計(jì)算示意圖RIP-2RIP-2的報(bào)文格式1：請(qǐng)求2：響應(yīng)0：沒(méi)有認(rèn)證2：密碼認(rèn)證密碼數(shù)據(jù)開(kāi)放式最短路徑優(yōu)先OSPFOSPF的特點(diǎn)用圖代表實(shí)際網(wǎng)絡(luò)并計(jì)算最佳路由OSPF中的一些概念OSPF中AS、主干和區(qū)域之間的關(guān)系OSPF中的工作原理鏈路狀態(tài)路由選擇算法的步驟了解相鄰節(jié)點(diǎn)測(cè)量線(xiàn)路代價(jià)（cost）構(gòu)造鏈路狀態(tài)分組發(fā)送鏈路狀態(tài)分組前圖中路前圖中路由器由器B的的分組緩沖分組緩沖區(qū)，包含區(qū)，包含新近到達(dá)新近到達(dá)還未處理還未處理完畢的分完畢的分組。組。計(jì)算新的路由最佳原理和接收

6、樹(shù)最短通路路由選擇算法利用Dijkstra算法求A到D的最短通路ABCEFGHD22164273223AB(2,A)E(,-)G(6,A)C(,-)F(,-)H(,-)D(,-)AB(2,A)E(4,B)G(6,A)C(9,B)F(,-)H(,-)D(,-)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(,-)D(,-)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(9,G)D(,-)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(8,F)D(,-)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(8,F)D(10,H)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(8,F)D(10,H)AB(2,A)E(4,B)G(5,E)C(9,B)F(6,E)H(8,F)D(10,H)最短通路為：A-B-E-F-H-D，權(quán)值為10OSPF報(bào)文類(lèi)型OSPF報(bào)文頭格式鄰居通信Hello協(xié)議報(bào)文Hello協(xié)議報(bào)文說(shuō)明數(shù)據(jù)庫(kù)描述報(bào)文鏈路狀態(tài)請(qǐng)求報(bào)文鏈路狀態(tài)更新報(bào)文鏈路狀態(tài)確認(rèn)報(bào)文LSA頭路由器LSA路由器LSA說(shuō)明OSPF的虛鏈路和傳輸網(wǎng)絡(luò)網(wǎng)絡(luò)LSA匯總LSAAS外部LSA邊界網(wǎng)關(guān)協(xié)議BGPBGP網(wǎng)絡(luò)的組成部份BGP的概念I(lǐng)BGP與EBGP通信BGP報(bào)文的頭OPEN報(bào)文UPDATE報(bào)文NOTIFICAT