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All areas in an Open Shortest Path First (OSPF) autonomous system must be physically connected to the backbone area (Area 0). does it mean do all the data really have to traverse through area 0, and it's part of area 0's duty to distribute inter area LSAs from one area to another? how making this star topology, I mean the urge of connecting other areas to area 0 gonna guard against routing loops within a multi-area network? is it about making just control-plane information, or actual data gonna get through other areas just by area 0?