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New Member


If the company has 10 locations throughout the world and the Data Center in USA. You design OSPF in a way that USA routers are in Area 0 and branches throughout the world in Area 1 for the Branch in Germany, Area 2 for the branch in France and so on. If someone in Germany has to communicate with a user France then the packets must come to USA and transit through OSPF Area 0. Is this an optimal design that requires packet to come all the way to USA then back to Europe.

I guess what I am saying since all areas are required to go through backbone area 0 but how to avoid the situation I described above.

Hall of Fame Super Silver


Hello Abbas,

with OSPF if you haven't a direct link between branch routers you would go through central site even if you have all router in a single area.

You would need to use a L2 VPN service to build a Virtual LAN that spans on all branches and central site and to have this in area 0.

If you can do this all branch routers are ABR for their site and branch to branch communication is possible.

If traffic volumes are no high you can think of deploying OSPF over a DMVPN allowing dynamic spoke to spoke to tunnel that again will build a virtual LAN for HUB routers and branch routers using simple internet access on each site.

Hope to help


Hall of Fame Super Silver



If we knew more about the environmemnt that you are working with we could give you better answers. You describe area 0 as being in USA, area 1 as Germany, area 2 as France, and so on. Is there a physical link between router(s) in Germany and router(s) in France? If so what area would you put them in?

It seems to me that your design puts area 0 in USA and all Area Border Routers in USA. Perhaps a better design would be to make the Area Border Router be routers in Germany, France, and so on. This would allow the links between Germany and France to be in area 0 and would allow Germany to communicate directly with France without needing to go through USA.



New Member



That is exactly what I was looking for. Totally True the ABR will have links to the local area as well as link to area 0 and that would eliminate traffic to traverse to USA and then back to Europe.