# Optimization of the AODV-Based Packet Forwarding Mechanism for BLE Mesh Networks
## 6 Conclusions  
This article presents the proposed O-AODV protocol for BLE mesh networks and its implementation on a testbed in comparison with the AODV and mesh protocols.  
There were various challenges with the experimental approach that are worth noting. One of the issues we faced was the lack of a simulation environment, which prevented us from testing for a high number of nodes because with physical devices, it was difficult to scale the experiments to a large number of nodes. The transmission power of the nodes was also lowered to limit the testbed to a more manageable size of 20 m \(\times\) 20 m. Finally, radio interference is an environmental factor that is difficult to eliminate in a physical testbed. This was reduced as much as possible by locating the tested in an area with minimal cochannel interference from WiFi access points and other wireless devices.  
Coming to the result outcome of this research, in terms of the PDR, the proposed protocol (84%) performed better than AODV, but not to the level of the mesh protocol. Moreover, the developed protocol outperformed AODV and mesh in terms of overheads, end-to-end one-way delays, and average per-hop delays. Furthermore, the proposed protocol had a lower RREQ-RREP setup time than the previous protocol version.  
The proposed optimization in O-AODV managed to reduce the delay to 5300 ms, which was less than the delays for AODV (6200 ms) and flooding mesh (7200 ms); while the overheads were also reduced to 22%, compared to the overheads for the AODV (42%) and flooding mesh (80%) protocols. Nonetheless, the PDR performance needs to be improved. In order to reduce the 10% difference in the PDR to be on par with the mesh protocol performance, enhancements such as multipath support for AODV to increase redundancy and ensure faster route recovery need to be investigated as the next step.  
Furthermore, the reduced delays and overheads will undoubtedly benefit the hospital scenario, as hospitals deal with emergencies all of the time, and delays can have a significant impact on response time during emergencies. Furthermore, lowering the overheads will benefit the network by putting less load on it, as shown in the Figure 20. In addition, there is room for improvement in PDR to bring it on par with the mesh protocols for improved reliability, since applications requiring high reliability will need to retransmit data due to packet loss, decreasing the available traffic capacity and limiting the ability to scale the network to a larger number of nodes.  
[PERSON] and [PERSON] developed and implemented the proposed protocol, as well as compiled the paper. [PERSON], [PERSON], [PERSON], and [PERSON] all contributed to the selection of the paper, its organization, critical assessment, and manuscript drafting. The published version of the manuscript has been read and approved by all authors. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors declare no conflict of interest.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} AC & Advertising Channel \\ AFH & Adaptive Frequency Hopping \\ AODV & Ad hoc On-demand Distance Vector \\ ATT & Attribute Protocol \\ BLE & Bluetooth Low-Energy \\ DC & Data Channel \\ DSDV & Destination-Sequenced Distance Vector \\ \end{tabular}