江苏省徐州机电高等职业学校 毕业论文
摘 要
采用MPLS技术组建的IP主干网对VPN有着有力的支持，MPLS技术可以在二、三层上实现VPN，但两种方法各有优缺点。文中描述了MPLS隧道技术的主要思想，分析了基于MPLS技术的二、三层VPN工作机制，比`较了MPLS二、三层VPN的工作特点．提出了要根据VPN网络设计性能和目标。合理选择基于MPLS技术的VPN方案组建所需要的VPN。
关键词：MPLS； 隧道技术； 二层VPN； 三层VPN
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江苏省徐州机电高等职业学校 毕业论文
Abstract
IP backbone network based on MPLS provides a powerful backing for VPN．Though a VPN could be setup in layer2 or layer3,there ale advantages and disadvantages for both.Describes the main idea of MPLS tunnel
technology．Analyzes the mechaIlism of layer2 and layer3 VPN based on MPLS．Comparesthe characteristics which ale possesd by hyer2 and hyer3 VPN．Proposes that on the basis of the property and target of network design a plan may be reasonably choosed to cornstruct the MPLS VPN needed by customers．
Key Words：MPLS；tunnel technology；layer2 VPN；layer3 VPN
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江苏省徐州机电高等职业学校 毕业论文
目 录
1.可行性分析 ................................................................................................................ 5 1.1 需求分析 ................................................................................................................ 5 1.2 经济可行分析 ....................................................................................................... 6 2.MPLS网络架构设计与关键技术研究 .......................................................................... 7 2.1 MPLS 网络设计思想 .............................................................................................. 7 2.3 网络设计拓扑 ........................................................................................................ 8 2.4 MPLS ............................................................................................................................ 9 2.4.1 MPLS架构中的设备分类 .................................................................................. 10 LSR: .......................................................................................................................... 10 LER： ....................................................................................................................... 10 ATM-LSR： .............................................................................................................. 11 ATM-LER： .............................................................................................................. 11 FEC： ....................................................................................................................... 11 LSP： ....................................................................................................................... 11 2.4.2 MPLS标签栈头部 .............................................................................................. 11 2.4.3 MPLS数据包转发与标签交换路径 .................................................................. 12 2.4.4标签的绑定与分发 ............................................................................................ 13 2.4.5倒数第二跳弹出（PHP,Penultimate Hop Popping） ....................................... 14 2.5 VRF ......................................................................................................................... 15
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基于MPLS的VPN网络设计
