In recent times, the Internet of Things (IoT) applications, including smart transportation, smart healthcare, smart grid, smart city, etc. generate a large volume of real-time data for decision making. In the past decades, real-time sensory data have been offloaded to centralized cloud servers for data analysis through a reliable communication channel. However, due to the long communication distance between end-users and centralized cloud servers, the chances of increasing network congestion, data loss, latency, and energy consumption are getting significantly higher. To address the challenges mentioned above, fog computing emerges in a distributed environment that extends the computation and storage facilities at the edge of the network. Compared to centralized cloud infrastructure, a distributed fog framework can support delay-sensitive IoT applications with minimum latency and energy consumption while analyzing the data using a set of resource-constraint fog/edge devices. Thus our survey covers the layered IoT architecture, evaluation metrics, and applications aspects of fog computing and its progress in the last four years. Furthermore, the layered architecture of the standard fog framework and different state-of-the-art techniques for utilizing computing resources of fog networks have been covered in this study. Moreover, we included an IoT use case scenario to demonstrate the fog data offloading and resource provisioning example in heterogeneous vehicular fog networks. Finally, we examine various challenges and potential solutions to establish interoperable communication and computation for next-generation IoT applications in fog networks.

近年来，物联网（IoT）应用不断涌现，包括智能交通、智能医疗、智能电网、智能城市等。生成大量实时数据用于决策。在过去的几十年里，实时传感数据已经通过可靠的通信渠道卸载到集中式云服务器进行数据分析。然而，由于终端用户与集中式云服务器之间的通信距离较长，网络拥塞、数据丢失、延迟和能源消耗增加的可能性越来越大。为了应对上述挑战，雾计算出现在分布式环境中，将计算和存储设施扩展到网络边缘。与集中式云基础设施相比，分布式雾框架可以在使用一组资源受限的雾/边缘设备分析数据的同时，以最小的延迟和能耗支持对延迟敏感的物联网应用程序。因此，我们的调查涵盖了雾计算的分层物联网架构、评估指标和应用方面及其在过去四年中的进展。此外，本研究还涵盖了标准雾框架的分层架构和利用雾网络计算资源的不同最新技术。此外，我们还包括一个物联网用例场景来演示异构车辆雾网络中的雾数据卸载和资源配置示例。最后，我们研究了各种挑战和潜在的解决方案，以在雾网络中为下一代物联网应用建立可互操作的通信和计算。本研究涵盖了标准雾框架的分层架构和利用雾网络计算资源的不同最新技术。此外，我们还包括一个物联网用例场景来演示异构车辆雾网络中的雾数据卸载和资源配置示例。最后，我们研究了各种挑战和潜在的解决方案，以在雾网络中为下一代物联网应用建立可互操作的通信和计算。本研究涵盖了标准雾框架的分层架构和利用雾网络计算资源的不同最新技术。此外，我们还包括一个物联网用例场景来演示异构车辆雾网络中的雾数据卸载和资源配置示例。最后，我们研究了各种挑战和潜在的解决方案，以在雾网络中为下一代物联网应用建立可互操作的通信和计算。