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CE routers are deployed in ring topology


The PE to PE are already in place, MPLS/L3VPN. Now, we are going to deploy several CE routers. However, they are deployed in ring topology via fiber network. The routers we bought are ASR9006. 

How can I deploy BGP for CE-PE, considering we do not have separate L2 network, CEN, or MSPP?



Everyone's tags (1)
Cisco Employee

Hi, Request you to attach



Request you to attach network diagram to make it more clear. If i am getting it correct all CE routers are connected in a ring and ring is getting terminated on PE. And each CE will be having LAN to connect end users. In this topology one CE will be used in data forwarding for other CE's customers and in case one port on PE goes down all traffic will transit from one CE directly connected to PE. This may cause high CPU. Please share clear requirement of your design.


- Akash



Hi Akash,Thank you for your

Hi Akash,

Thank you for your reply. Attached is the diagram.

Yes, LAN will be connected to CE. CE's are connected to PE's via BGP. CE's not directly connected to PE, will pass through other CE's with physical connection to PE.




Cisco Employee

 Hi, Establishing BGP between




Establishing BGP between CE and PE is not a problem. You can have multi-hop eBGP between CE loopback and PE loopback or you have establish eBGP between PE and directly connected CE and then iBGP between CEs. But my only concern is that one CE will act as transit for other CE. Cant we have DWDM ring on layer 2 and connect CE to DWDM ring. What device you are using as CE and how much traffic is expected on that ring.



Hello,Unfortunately, there


Unfortunately, there will be no DWDM on access or aggregation rings. ASR9006 for access rings, and ASR9010 for aggregation rings. All fiber will terminate directly to routers. Is it possible to establish L2VPN sitting below BGP in these equipment? Is this advisable?





Cisco Employee

 Hi,for setting up L2VPN



for setting up L2VPN between CE and PE, requirement not clear to me. Depends what services you are offering to end customers. If they are using just internet service, to get full/partial/default route BGP should be sufficient and any IGP protocol you can run for reachability to BGP next-hop



Hello Akash,The network will

Hello Akash,

The network will be solely for wireless service provider network (2G/3G). There will be no external customers. Node at the CE premises will communicate to elements at Core location (Data Center), and there will also be nodes at CE which will directly communicate to other CE nodes. There are numerous VRFs, and 2 or 3 Data Centers. 



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