🤖 AI Summary
To address disrupted emergency communication caused by traditional infrastructure failure after disasters, this paper proposes a resilient emergency communication architecture leveraging existing smart-city IoT infrastructure. Methodologically, it innovatively integrates Wi-Fi HaLow (IEEE 802.11s) multi-hop mesh networking, Software-Defined Networking (SDN), and a LoRa-based flooding control plane: the former enables high-reliability, low-latency multimodal interaction (audio/video, text, location), while the latter supports wide-area, low-power, adaptive remote network management. Experimental evaluations in complex urban environments demonstrate that the Wi-Fi HaLow mesh achieves average end-to-end latency of 15–54.8 ms and throughput in the hundreds of kbps; LoRa control-message delivery success rate reaches 94.96%. The architecture significantly enhances post-disaster communication robustness, manageability, and heterogeneous system interoperability.
📝 Abstract
Events such as catastrophes and disasters are, in most cases, unpredictable. Consequently, reusing existing infrastructures to develop alternative communication strategies after disasters is essential to minimise the impact of these events on the population's ability to communicate and promptly receive alerts from authorities. In this context, the emergence of smart cities, characterised by dense and geographically distributed IoT networks, presents significant potential for such reuse. This work proposes HaLert, a resilient architecture for smart cities based on a Wi-Fi HaLow IEEE 802.11s mesh network, whose resources can be readily reallocated to support a emergency communication system to exchange messages (including text, location, image, audio, and video) between citizens, authorities, and between both parties. To facilitate remote monitoring and configuration of the network, the architecture incorporates the SDN (Software-Defined Networking) paradigm, supported by a LoRa controlled flooding mesh network. A prototype was developed based on this architecture and tested in a real urban scenario comprising both indoor and outdoor environments. The results demonstrated that, despite the significant impact of obstacles, lack of line-of-sight, and terrain slopes on the latency (average latency between 15 and 54.8 ms) and throughput (upload bitrates between 134 and 726 Kbps and download bitrates between 117 and 682 Kbps) of the Wi-Fi HaLow network, it remained stable and resilient, successfully providing all functionalities associated with the HaLert architecture. The tests conducted on the LoRa network revealed a high average message success rate of 94.96%.