Инструкции По Установке для 3com S7906E

 

1-6 

5)  CE 2 transmits the packet to the destination by IP forwarding. 

In MPLS L3VPNs, VPN target attributes are used to control the advertisement and reception of VPN 

routes between sites. They work independently and can be configured with multiple values to support 

flexible VPN access control and implement multiple types of VPN networking schemes. 

In the simplest case, all users in a VPN form a closed user group. They can forward traffic to each other 

but cannot communicate with any user outside the VPN. 

For this networking scheme, the basic VPN networking scheme, you need to assign a VPN target to 

each VPN for identifying the export target attribute and import target attribute of the VPN. Moreover, this 

VPN target cannot be used by any other VPNs.  

Figure 1-4 Network diagram for basic VPN networking scheme 

 

 

, for example, the VPN target for VPN 1 is 100:1 on the PEs, while that for VPN 2 is 200:1. 

The two VPN 1 sites can communicate with each other, and the two VPN 2 sites can communicate with 

each other. However, the VPN 1 sites cannot communicate with the VPN 2 sites. 

For a VPN where a central access control device is required and all users must communicate with each 

other through the access control device, the hub and spoke networking scheme can be used to 

implement the monitoring and filtering of user communications.  

This networking scheme requires two VPN targets: one for the "hub" and the other for the "spoke".  

The VPN target setting rules for VPN instances of all sites on PEs are as follows: 

z 

On spoke PEs (that is, the PEs connected with spoke sites), set the export target attribute to Spoke 

and the import target attribute to Hub. 

z 

On the hub PE (that is, the PE connected to the hub site), specify two interfaces or sub-interfaces, 

one for receiving routes from spoke PEs, and the other for advertising routes to spoke PEs. Set the 

import target attribute of the VPN instance for the former to Spoke, and the export target attribute of 

the VPN instance for the latter to Hub.