MPLSVPN基本概念.ppt

VRF RT RT的本质 RT的灵活应用 RD(Route Distinguisher) RD的本质 三个概念总结 省网RD/RT规划 本规范要求各地市在业务开展中，RD 采用的格式为：ASN:32 比特数字。其中ASN 必须各地市自己的AS 号码，对于VPN业务的RD，采用以下具体要求： 省公司VPN业务RD: 64920:XXX IPTV业务 RD:64920:999 （全省统一规划） NGN 业务RD: 655XX:10YYY （655XX为地市城域网AS号，YYY为PE Loopback地址最后一段的数字） 各城域网VPN业务的RD: 655XX:11ZZZ（655XX为地市城域网AS号，ZZZ为各地市根据自己的VPN发展情况自行规定，取值从001-999，每开设一个VPN业务，在PE上设定一个统一的RD） 例：如果沈阳城域网的一个PE的loopback为123.189.224.32，承载NGN信令的VPN，规划该PE所使用RD规划为65500:10032。 省网RD/RT规划 通常情况下RT与RD使用相同的参数进行标记。在需要VPN之间配置各种路由策略时，对RT的export和import参数可由各地市针对需求分别进行灵活配置。省公司VPN业务的RT由省公司统一设置。 Outline PE如何转发VPN包穿越骨干网？ PHP工作方式？ PE如何得到VPN的标签？ What are the Effects of MPLS VPNs on Label Propagation? What are the Effects of MPLS VPNs on Packet Forwarding? Lesson Summary PE如何转发VPN包穿越骨干网？ PE如何转发VPN包穿越骨干网？ VPN Penultimate Hop Popping VPN Label Propagation VPN Label Propagation (Cont.) 概述 PE routers forward packets across the MPLS VPN backbone using label stacking. The last P router in the LSP tunnel pops the LDP label, and the PE router receives a labeled packet that contains only the VPN label. Labels are propagated between PE routers using MP-BGP. LDP labels are not assigned to BGP routes. VRF 配置任务 VRF configuration tasks: Create a VRF table. Assign RD to the VRF. Specify export and import route targets. Assign interfaces to VRFs. Specifying Export and Import RTs Specifying Export and Import RTs (Cont.) Assigning an Interface to VRF Table MPLS VPN Network Example MPLS VPN Network Example (Cont.) 配置 BGP Address Families The BGP process in an MPLS VPN-enabled router performs three separate tasks: Global BGP routes (Internet routing) are exchanged as in traditional BGP setup. VPNv4 prefixes are exchanged through MP-BGP. VPN routes are exchanged with CE routers through per-VRF EBGP sessions. Address families (routing protocol contexts) are used to configure these three tasks in the same BGP process. Configuring BGP Address Families (Cont.) Configuring MP-BGP MPLS VPN MP-BGP configuration steps: Configure MP-BGP neighbor