3com S7906E 설치 설명서

 

1-5 

An S7900E switch with MCE enabled can solve this problem. By binding the VLAN interfaces to the 

VPNs in a network on an S7900E switch of this kind, you can create and maintain a routing table for 

each of the VPNs. In this way, packets of different VPNs in the private network can be isolated. 

Moreover, with the cooperation of the PE, the routes of each VPN can be advertised to the 

corresponding remote PE properly, so that packets of each VPN in the private network can be 

transmitted securely through the public network.  

 illustrates how MCE creates and maintains routing entries of multiple VPNs and how the 

MCE exchanges VPN routes with PEs.  

Figure 1-3 How MCE works 

 

 

In 

, the two VPN sites on the left side (Site 1 and Site 2) are connected to the backbone 

network through an MCE device. Two VPN tunnels are expected between them and the remote VPNs 

at Site 2 and Site 1.  

With MCE enabled, routing tables can be created for VPN 1 and VPN 2 individually, VLAN-interface 2 

can be bound to VPN 1, and VLAN-interface 3 can be bound to VPN 2. When receiving a piece of 

routing information, MCE determines the source of the routing information according to the number of 

the interface receiving the information and then maintains the corresponding routing table accordingly.  

You need to also to bind the interfaces to the VPNs on PE 1 in the same way as those on the MCE 

device. The MCE device is connected to PE 1 through a trunk, which permits packets of VLAN 2 and 

VLAN 3 with VLAN tags carried. In this way, PE 1 can determine the VPN a received packet belongs to 

according to the VLAN tag of the packet and passes the packet to the corresponding tunnel.  

Interface-to-VPN-instance binding enables CEs and PEs to determine the sources of received packets 

and then forward the packets according to the routing information concerning the corresponding VPNs. 

The following sections describe the way how MCE transmits the private routing information of multiple 

VPNs to PEs properly.  

A CE can adopt the following routing protocols to exchange VPN routes with a site: