## 5 Experiments and Results
### F&C versus Other Repeal-Based Flooding Protocols  
Now we present a comparison between F&C and other repeal-based flooding schemes. BERS [12], tBERS, and tBERS* [17] were selected for this analysis since they are protocols comparable to F&C since they chase the initial flooding once the source and target nodes find each other. To evaluate the performance of such protocols and compared them to F&C, we performed simulations in SimPy [34]. Figure 13 shows the results of the simulation of such protocols in terms of signaling overhead and resource discovery delay, respectively. The simulation parameters are the same as before (see Table 5).  
The plots in Figure 13 show that BERS generates a ring search that minimizes the flooded area for nodes close to the source. Nevertheless, the ring search technique increases the resource discovery delay shown in Figure 13b. tBERS, on the other hand, repeals the flooding in a target node, reducing  
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Ideal Condition** & \multicolumn{2}{c}{**Non-Ideal Condition**} \\ \hline shape & 65\% (disk) & \multicolumn{2}{c}{72\% (irregular)} \\ \hline density & 65\% (uniform) & 61\% (higher density) & 70\% (lower density) \\ \hline mobility & 65\% (static) & 60\% (1 min) & 75\% (10 min) \\ \hline \hline \end{tabular}
\end{table}
Table 6: F&C signaling under ideal and non-ideal conditions.  
Figure 12: F&C under non-ideal conditions. (**a**) Irregular network shape; (**b**) Mobility: After nodes moved during 1 min; (**c**) Mobility: After nodes moved during 10 min.  
the number of signaling packets needed to find it. Despite this, the delay remains the same as in BERS. An improvement was made in tBERS* by reducing 50% the retransmission delay, thus halving the resource discovery delay while slightly increasing the signaling overhead. The plots in Figure 13a show that the signaling packets generated by BERS, tBERS, and tBERS* can surpass the number generated by traditional flooding as the route hop count increases. In the worst case, these protocols can generate twice as many signaling packets than traditional flooding when the source and target nodes are far from each other.  
F&C behaves similarly to the BERS family of protocols before the route hop-count to the resource reaches the target's repeal-flooding boundary and behaves similar to traditional flooding afterward (i.e., no attempt is made to chase the initial flooding). As a result of this behavior, F&C's signaling increases with the hop count, up to a point it remains similar to traditional flooding. Figure 13, more than any other figure, shows the key distinctive feature of F&C over other repeal-based protocols. In terms of delay, F&C with \(\Delta_{t}=4\delta\) behaves linearly with the route hop count to the resource while being slower than tBERS* before nine hops, improving afterward. When F&C uses variable \(\Delta_{t}\), i.e., \(\Delta_{t}=var\), the delay behaves as tBERS* before 13 hops and starts improving after that point. Notice that F&C with \(\Delta_{t}=var\) improves F&C with \(\Delta_{t}=4\delta\) in terms of overhead since the hill found around nine hops is smaller than for the other protocols.