Setup Phase

1. The destination node initiates the connection by flooding the network in the direction of the source node or region. It also sets the "cost" field to zero before sending the request.

2. Every intermediate node forwards the request only to neighbors closer to the source node (region) and farther away from the destination node than itself. Thus, at a node N,, the request is sent only to a neighbor Nj that satisfies:

d (Ni,Ns) > d (Nj, Ns) d (Ni, Nd ) < d (Nj, Nd )

3. Upon receiving the request, the energy metric for the neighbor that sent the request is computed and is added to the total cost of the path. Thus, if the request is sent from node Nj to node Nj, Nj calculates the cost of the path as:

4. Paths that have a very high cost are discarded and not added to the forwarding table. Only the neighbors Nj with paths of low cost are added to the forwarding table FTj of Nj.

5. Node Nj assigns a probability to each of the neighbors Nj in the forwarding table FTj, with the probability inversely proportional to the cost.

6. Thus, each node N. has a number of neighbors through which it can route packets to the destination. Nj then calculates the average cost of reaching the destination using the neighbors in the forwarding table.

7. This average cost, Cost(Nj) is set in the "cost" field of the request packet and forwarded along toward the source node, as in step 2.

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