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Example of Essential CDS Algorithm Node numbers indicate RIDs. Thin lines indicate neighbors. Red nodes indicate DRs. Green nodes indicate BDRs. Red lines indicate adjacencies associated with DRs, which form a tree in this case. Green lines indicate adjacencies added to form a biconnected subgraph. Note that each non-DR/BDR node is adjacent to one DR and one BDR (or a 2nd DR). For example, node 6 does not select itself as DR, since there is a path from node 8 to each other neighbor via nodes with larger ID. But node 6 selects itself as BDR, since there do not exist two such paths from node 8 to neighbors 2, 3, 4, and 7. 1 7 8 4 3 6 5 2 |