Cloud Computing: Architectures, Service Models, Security, and Emerging Trends

Abstract

Cloud computing has become the default infrastructure for modern software delivery, with the large majority of new digital workloads now built on cloud-native platforms rather than on-premises hardware. This paper surveys the current state of cloud computing: its foundational service models (Infrastructure-, Platform-, and Software-as-a-Service), deployment models (public, private, hybrid, and multi-cloud), and the architectural shift toward containerization and serverless computing. It reviews the security landscape, where misconfiguration and identity-related failures, not exotic exploits, remain the dominant cause of breaches, and surveys the shift toward zero-trust architectures and cloud-native application protection platforms. It further examines the growing entanglement of cloud computing with artificial intelligence, both as a workload that is reshaping infrastructure demand and as a tool used for security and operations, and reviews the environmental costs of cloud growth alongside emerging sustainability practices such as carbon-aware scheduling and energy-efficient serverless design. The paper closes with a discussion of open challenges, including multi-cloud complexity, the widening skills gap, and the tension between rapid AI-driven infrastructure growth and sustainability commitments