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MDR Selection Algorithm (slide 1 of 2) Phase 1 – Create the Neighbor Connectivity Matrix Matrix used to identify bidirectional neighbors Phase 2 – MDR and Dependent Neighbors Selection Runs in O(d2) time using BFS to compute paths from the neighbor with largest value of (MDR Level, RtrPri, RID) to the other neighbors, using only neighbors with a larger value of (MDR Level, RtrPri, RID) as intermediate nodes. MDRConstraint: (default 3) constrains the number of hops allowed in the computed paths. A smaller value (2) results in a larger CDS with a smaller stretch factor. MDR Level: Gives priority to existing MDRs for increased stability (similar to OSPF’s DR election algorithm). RtrPri: Can depend on bandwidth capacity, battery life, node degree, neighbor stability, etc. RtrPri can also be changed dynamically to share the burden of being an MDR among all routers. Dependent Neighbors: Used to determine which MDR neighbors to become adjacent with, to ensure the backbone of MDRs is connected. |