BGP协议基础PPT教程.ppt

BGP（Border Gateway Protocol）;缺点1：没有发现路由环路的能力 缺点2：不支持复杂的基于策略的路由 缺点3：不能充分地与IGP互相合作 缺点4：公布网络变化相当慢;Internet;BGP工作方法摘要;Internet;BGP邻居关系的建立-AS号;BGP邻居关系的建立-状态机;BGP邻居关系的建立-消息;BGP邻居关系的建立-Open消息格式;Unfeasible Route Length (2 bytes);;AS100;AS 3;AS 3;Router A(config)# show ip bgp nei BGP neighbor is 200.200.13.2, remote AS 100, local AS 100, internal link BGP version 4, remote router ID 2.2.2.2 BGP state = Established, up for 00:00:06 Last read 00:00:06 Hold time is 180, keepalive interval is 60 seconds Neighbor capabilities: Route refresh: advertised and received (old and new) Address family IPv4 Unicast: advertised and received Received 2 messages, 0 notifications, 0 in queue Sent 4 messages, 0 notifications, 0 in queue1, 0 in queue2;AS 3;R4;R4;AS 3;AS 3;AS 3;BGP进阶-同步开关（续）;AS 3;AS 3;AS 3;r2;??聚合前R1上的路由： r011(config)# show ip bgp BGP table version is 0, local router ID is 172.17.1.1 Status codes: s suppressed, d damped, h history, * valid, best, i - internal Origin codes: i - IGP, e - EGP, ? - incomplete Network Next Hop Metric LocalPrf Path *i172.17.2.2/32 172.17.123.2 2 100 ? *i172.17.3.3/32 172.17.3.3 0 100 ? *i172.17.4.4/32 172.17.34.4 2 100 ? *i172.17.5.5/32 172.17.35.5 1 100 ? *i172.17.34.0/24 172.17.3.3 0 100 ? *i172.17.35.0/24 172.17.3.3 0 100 ? *i172.17.123.0/24 172.17.3.3 0 100 ? * 172.17.210.210/32 0.0.0.0 0 i *i172.17.220.220/32 172.17.2.2 100 i *i172.17.230.230/32 172.17.3.3 100 i Total number of prefixes 10;未聚合前R6上的路由： r052(config)# show ip bgp BGP table version is 0, local router ID is 172.21.2.2 Status codes: s suppressed, d damped, h history, * valid, best, i - internal Origin codes: i - IGP,