10.6 Parameter Optimization
In this section, we optimize two parameters in OppCast: the forwarding range FR and threshold density ρth.
10.6.1 Optimize the Forwarding Range
As mentioned in Section 10.5.1, the goal here is to minimize the expected total number of transmissions E[NT]. Stated formally, we want to find the FR
Algorithm 10.1 Distributed OppCast algorithm running at node u
Input: Node u receives a WM m; If u is in the IR of m, and m is a new packet If typeprevhop = forwarder and xu > xright //Enter FFD; If (xu − xright) < the local optimal boundary range (LBR) Set xD = xright + LBR, xI = xright; //the RCR Compute Δtu and run OBCF; //potential forwarder If u becomes a forwarder Use to compute the new local optimal boundary range;
Set xleft = xright, xright = xu; Increase the one-hop zone index by 1 and broadcast m. If xleft < xu < xright //potential makeup If typeprevhop = forwarder //Initialize MFR Makeup node level = 0; sub-zone index μ = 0;
If , then exit;