# On Sharing an FIB Table in Named Data Networking
## 4 Performance Evaluation
### Performance Comparison with Other Schemes
Overall, these results indicate that the proposed algorithm is highly scalable. Figure 9: Comparison in average hop count. The proposed scheme can achieve the near optimal packet delivery in all four topologies. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Shortest Path** & **Flooding** & **The Proposed** \\ \hline Number of FIB entries & 191,000 & 91,008 & 9054 \\ Number of total characters & 9,365,303 & 4,452,560 & 449,800 \\ Number of Bloom filters & - & - & 457 \\ \hline Memory using Equation (4) (MB) & 9.11 & 6.88 & 0.55 \\ Ratio & 1 & 0.75 & 0.06 \\ \hline Memory using Equation (5) (MB) & 4.00 & 2.34 & 0.26 \\ Ratio & 1 & 0.75 & 0.08 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Memory consumption of AS-3967 \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Shortest Path** & **Flooding** & **The Proposed** \\ \hline Number of FIB entries & 162,000 & 126,798 & 8769 \\ Number of total characters & 7,943,346 & 6,218,337 & 438,261 \\ Number of Bloom filters & - & - & 370 \\ \hline Memory using Equation (4) (MB) & 7.73 & 5.89 & 0.52 \\ Ratio & 1 & 0.76 & 0.07 \\ \hline Memory using Equation (5) (MB) & 2.63 & 2.01 & 0.23 \\ Ratio & 1 & 0.76 & 0.09 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Memory consumption of AS-1775. Figure 10: Comparison in the normalized number of _Interest_ packets. The proposed scheme uses only about 1% more _Interest_ packets than the _shortest path_, while simple _flooding_ consumes up to almost twice the number of _Interest_ packets. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Shortest Path** & **Flooding** & **The Proposed** \\ \hline Number of FIB entries & 175,000 & 75,394 & 6133 \\ Number of total characters & 8,580,775 & 3,694,688 & 308,835 \\ Number of Bloom filters & - & - & 327 \\ \hline Memory using Equation (4) (MB) & 8.35 & 3.60 & 0.38 \\ Ratio & 1 & 0.43 & 0.05 \\ \hline Memory using Equation (5) (MB) & 2.83 & 1.22 & 0.17 \\ Ratio & 1 & 0.43 & 0.06 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Memory consumption of AS-6461. Figure 11 graphically compares the memory consumption, which is normalized by the memory consumption of the _shortest path_ for the \(Mem_{2}\) case shown in Equation (5). It is shown that the proposed work consumes only 5-9% of the memory consumed by the _shortest path_. In our proposed work, every producer and every node which receives name prefix broadcasting from other networks needs to propagate an S-BF which contains the connectivity information. The traffic caused in propagating the connectivity information is shown in Equation (6), where \(N_{pro}\) is the number of producers, \(S_{BF}\) is the size of the S-BF, and \(N_{l}\) is the number of the entire links in a network. \[T_{P}=N_{pro}\cdot S_{BF}\cdot N_{l} \tag{6}\]  
For link state algorithms, the pair of name prefix and its cost should be propagated in order to create an FIB table. Equation (7) shows the traffic, where \(N_{pfx}\) is the number of name prefixes and \(S_{pfx}\) is the size of each name prefix. \[T_{LS}=\sum_{i=1}^{N_{pfx}}S_{pfx}\cdot N_{l} \tag{7}\]  
Figure 12 compares the traffic amounts for routing. Because the traffic amounts for routing are related to the number of links in the network, more traffic is required for the networks with more complicated connections. Hence, the amount of consumed traffic is minimum for AS-6461. While the _shortest path_ scheme propagates the individual connectivity information, the proposed scheme spreads the summary of the connectivity information in the form of a Bloom filter. Therefore, the traffic used for the proposed work is much smaller than _shortest path_, which is about 6-8% of the traffic of the _shortest path_. Figure 11: Comparison in memory consumption (\(Mem_{2}\)). The proposed work consumes only 5–9% of the memory consumed by the _shortest path_, of which routers have the complete knowledge of all name prefixes.