An Edge-Cloud Hybrid Architecture for Integrating Standalone and Web Applications in Mission-Critical Systems

Standalone applications are widely deployed in mission-critical environments due to their high execution speed, reliability, and ability to operate without continuous network connectivity. In contrast, web-based applications offer scalability, centralized data management, and ubiquitous accessibility, but often suffer from latency, offline limitations, and dependency on network availability. Relying exclusively on either paradigm is insufficient for modern enterprise systems that demand both responsiveness and scalability. This paper presents an edge-cloud hybrid software architecture that integrates standalone and web applications to achieve offline resilience, centralized coordination, and scalable collaboration. In the proposed framework, an edge-based local application performs time-sensitive operations and maintains persistent local storage, while a cloud-backed server manages global synchronization, multi-user access, and security enforcement. A conflict-aware synchronization mechanism based on RESTful services and distributed consistency principles ensures reliable data convergence across heterogeneous environments. The framework is implemented and experimentally evaluated using a hospital management system case study. Experimental results demonstrate low synchronization latency, stable resource utilization, and high fault tolerance under increasing workloads. The findings confirm that the proposed hybrid architecture effectively bridges offline and online computing, making it suitable for mission-critical domains such as healthcare, finance, and transportation.