# Location-Based Deferred Broadcast for Ad-Hoc Named Data Networking
## 5 Simulation Evaluation
### Evaluation Results  
At first, we evaluate the performance of satisfaction ratio of those broadcast schemes. Figure 8 shows that the satisfaction ratio of LBDB is lower than DASB and Rapid Forwarding, but higher than No FP timer and NAIF. DASB achieves the highest satisfaction ratio, which fits in with expectation. It is because some nodes in DASB may not cancel their pending interests upon receiving an interest which has the same name as the pending interests while other schemes will cancel its own pending interest transmission. Thus in DASB, interests have more opportunities to be forwarded to the potential data carrier. Satisfaction ratio of LBDB is a little lower than that of Rapid Forwarding. It indicates that in an urban area, a shortest path to data may not exist sometimes. Rapid Forwarding and DASB may choose father nodes from data to forward the interest. Thus they will have a little higher satisfaction ratio. However, LBDB does not lose too much satisfaction ratio because of this. It has much higher satisfaction ratio than No FP Timer and NAIF. We observe that more cars contribute to a higher satisfaction ratio, which is reasonable because the interests have more chances to be forwarded to the producer. We also find that more consumers result in lower satisfaction ratio. It is because more interests are issued when there are more consumers. Even though some interests can be satisfied by cached data, the total number of lost interest is still increasing.  
From the above analysis, we find that LBDB does not achieve highest satisfaction ratio among all broadcast schemes. The reason is that LBDB forwards interest toward data but sometimes the node nearest to the data is not on the path to the data. The actual path may be longer than the shortest path. Other protocols should not have this issue because the interest may be forwarded to all directions.  
Figure 8: Satisfaction Ratio.  
To verify our analysis, we measure the average of hops, which indicates how long the path is from consumer to produce then back the consumer. Figure 9 shows the results of average hops. We find that LBDB always results in the least hop count, which proves that LBDB always try to find the shortest path to the data. And interesting finding is that as the number of consumers increases, there comes more hops. It indicates that even though more interests can be satisfied by cache, increased interests need more hops to get satisfied.  
Next, we study the performance in terms of normalized transmission overhead. Figure 10 shows that LBDB has the least normalized transmission overhead among all the evaluated protocols. It means LBDB uses the least amount of bandwidth to provide the same data retrievals as the other protocols. The figure also shows that such advantage is more significant when the network is dense or there are less consumers. The reason is that LBDB takes consideration of data's location so the interest can be forwarded toward the data so redundant forwarding is reduced. The figure also shows that more cars (i.e., denser networks) incur more transmission overhead, which is expected as more cars participate in the forwarding process. On the other hand, when the number of consumers increases, transmission overhead is reduced. This is because more interests are satisfied by the caches. The result suggests that LBDB reduces the transmission overhead.  
Figure 11 presents the results of average delay. We notice that No FP Timer and NAIF show the shortest delays. This is because the two do not use FP timer, leading to reduced total waiting time. Rapid Forwarding and DASB use the same method to calculate FP deferred timer so their performance are similar. Our proposed LBDB has shorter average delay than Rapid Forwarding and DASB, which indicates that LBDB takes shorter time to satisfy interest than the existing works.  
Figure 10: Normalized Transmission Overhead (interest and data).  
Figure 9: Average Hops.