NFV

Network Functions Virtualization (NFV) is a network architecture concept that decouples network functions from dedicated hardware appliances by running them as software on general‑purpose servers and storage. NFV aims to improve agility, scalability, and cost efficiency by enabling rapid provisioning, updating, and scaling of services such as firewalls, load balancers, routers, and deep packet inspection engines through software and orchestration rather than physical devices. It is widely associated with the standards work of the ETSI NFV Industry Specification Group (ISG), which began in 2012.

An NFV architecture typically consists of three major elements: the NFV Infrastructure (NFVI), the Virtual Network Functions (VNFs), and the management and orchestration layer (MANO). NFVI covers the physical resources (compute, storage, and networking) and the virtualization layer. The Virtual Network Functions are software implementations of network functions that run on the NFVI. The MANO layer includes the NFV Orchestrator (NFVO), which coordinates network services and lifecycle management; the VNF Manager (VNFM), which handles deployment and scaling of individual VNFs; and the Virtualization Management (VIM), which allocates and monitors NFVI resources. Network Services (NS) are composed of connected VNFs, with descriptors such as VNF Descriptor (VNFD) and Network Service Descriptor (NSD) that define how VNFs are deployed and interconnected.

NFV is designed to work with, and often in combination with, software-defined networking (SDN), where SDN controls the forwarding plane while NFV provides the virtualized function implementations. National and industry deployments span telecom core networks, enterprise WANs, and emerging 5G infrastructures, including edge deployments and network slicing.

Standards and ongoing work focus on interoperability, lifecycle management, performance benchmarking, and security. While NFV offers flexibility and cost benefits, challenges include interoperability across vendors, management complexity, potential performance overhead, and security risks associated with multi-tenant virtualized environments.