基于MPLS的二、三层VPN研究

Research on L2 and L3 VPN Based on MPLS

传统的IP VPN采用封装技术在IP主干网上建立隧道,发送数据分组,MPLS采用在数据分组头部增加转发标签的技术,完成数据分组在IP主干网的转发。基于MPLS的VPN有两种实现方式,就是基于MPLS的二、三层VPN实现方案。文中阐述了MPLS网络的基本工作原理和MPLS主干网的结构,分析了基于MPLS技术的二、三层VPN的拓扑结构和工作机制,总结了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方案组建用户所需要的VPN。

The conventional forwards data packages by tunnel which is set up over IP backbone via encapsulated technology. MPLS makes use of labels added in the header of datagram to forward the data packets over IP backboe. There are two ways to realize the VPN based on MPLS, that is , the methods of hyer2 and layer3 VPN based on MPLS. States the main principle of MPLS technology and the structure of MPLS backbone. Analyzes the mechanism and topology of layer2 and layer3 VPN based on MPLS. Sunmmarizes the characteristics which are possesd by layer2 and layer3 VPN. Proposes that on the basis of the property and target of network design a plan may be reasonably choosed to construct the MPLS VPN needed by customers.