ospf-5----Page:2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
|
Basic Idea – Generalize Designated Router to Multihop Wireless Networks In an OSPF broadcast network, the DR and its adjacencies form a tree with n-1 edges. The DR is the only interior node of the tree, and is a connected dominating set (CDS). All nodes agree on a single DR, by selecting the node with largest (RtrPri, RID). In a multihop wireless network, a CDS can have multiple nodes. These are again the interior nodes of a spanning tree. The CDS nodes generalize the notion of a DR, and the edges of the spanning tree become the adjacencies. The set of DRs can again be kept small by selecting nodes with largest (RtrPri, RID). For faster convergence, the tree can be “approximate”, with more than n-1 edges, based on 2-hop neighbor information. |