Department of Computer Engineering, Bogazici University, 34342 Istanbul, Turkey.
Institute of Applied Information Technology (InIT), Zurich University of Applied Sciences (ZHAW), 8401 Winterthur, Switzerland.
Sensors (Basel). 2023 Feb 21;23(5):2375. doi: 10.3390/s23052375.
Under demanding operational conditions such as traffic surges, coverage issues, and low latency requirements, terrestrial networks may become inadequate to provide the expected service levels to users and applications. Moreover, when natural disasters or physical calamities occur, the existing network infrastructure may collapse, leading to formidable challenges for emergency communications in the area served. In order to provide wireless connectivity as well as facilitate a capacity boost under transient high service load situations, a substitute or auxiliary fast-deployable network is needed. Unmanned Aerial Vehicle (UAV) networks are well suited for such needs thanks to their high mobility and flexibility. In this work, we consider an edge network consisting of UAVs equipped with wireless access points. These software-defined network nodes serve a latency-sensitive workload of mobile users in an edge-to-cloud continuum setting. We investigate prioritization-based task offloading to support prioritized services in this on-demand aerial network. To serve this end, we construct an offloading management optimization model to minimize the overall penalty due to priority-weighted delay against task deadlines. Since the defined assignment problem is NP-hard, we also propose three heuristic algorithms as well as a branch and bound style quasi-optimal task offloading algorithm and investigate how the system performs under different operating conditions by conducting simulation-based experiments. Moreover, we made an open-source contribution to Mininet-WiFi to have independent Wi-Fi mediums, which were compulsory for simultaneous packet transfers on different Wi-Fi mediums.
在交通拥堵、覆盖范围问题和低延迟要求等苛刻的运营条件下，地面网络可能无法为用户和应用程序提供预期的服务水平。此外，当自然灾害或物理灾难发生时，现有的网络基础设施可能会崩溃，导致服务区域的紧急通信面临巨大挑战。为了在瞬态高服务负载情况下提供无线连接并促进容量提升，需要替代或辅助的快速部署网络。由于具有高机动性和灵活性，无人机 (UAV) 网络非常适合这种需求。在这项工作中，我们考虑了一个由配备无线接入点的无人机组成的边缘网络。这些软件定义的网络节点在边缘到云的连续环境中为移动用户的延迟敏感工作负载提供服务。我们研究基于优先级的任务卸载，以支持按需空中网络中的优先级服务。为此，我们构建了一个卸载管理优化模型，以最小化任务截止日期的优先级加权延迟引起的总体惩罚。由于定义的分配问题是 NP 难的，因此我们还提出了三种启发式算法以及一种分支定界风格的准最优任务卸载算法，并通过基于仿真的实验研究了在不同操作条件下系统的性能。此外，我们为 Mininet-WiFi 做出了开源贡献，以拥有独立的 Wi-Fi 介质，这对于不同 Wi-Fi 介质上的同时数据包传输是必需的。
