3com S7906E 설치 설명서

 

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5)  The VPN instance on PE 2 searches the MVRF and finally delivers the private network multicast 

data to Receiver. By now, the process of transmitting a private network multicast packet across the 

public network is completed.  

Multi-AS MD VPN 

If nodes of a VPNs network are allocated in multiple autonomous systems (ASs), these VPN nodes 

must be interconnected. Two approaches are available to implement multi-AS VPN:  

VRF-to-VRF PE interconnectivity 

As shown in 

, a VPNs network involves two ASs, AS 1 and AS 2. PE 3 and PE 4 are the 

autonomous system boundary router (ASBR) for AS 1 and AS 2 respectively. PE 3 and PE 4 are 

interconnected through their respective VPN instance and treat each other as a CE device.  

Figure 1-10 VPN instance-VPN instance interconnectivity 

 

 

In the VPN instance-VPN instance interconnectivity approach, a separate MD needs to be established 

within each AS, and VPN multicast traffic between different ASs is transmitted between these MDs.  

 

Because only VPN multicast traffic is forwarded between ASBRs, different PIM modes can run within 

different ASs. However, the same PIM mode (PIM-DM, PIM-SM, or PIM-SSM) must run on all 

interfaces that belong to the same VPN (including interfaces with VPN bindings on ASBRs).  

 

Multi-hop EBGP interconnectivity 

As shown in 

, a VPNs network involves two ASs, AS 1 and AS 2. PE 3 and PE 4 are the 

autonomous system boundary router (ASBR) for AS 1 and AS 2 respectively. PE 3 and PE 4 are 

interconnected through their respective public network instance and treat each other as a P device.