VNF
Virtualized Network Function: a network function implemented as software running on virtual machines or containers in a cloud infrastructure, replacing dedicated hardware appliances.
A VNF is a network function delivered as software you run on shared infrastructure instead of a purpose-built appliance. Take a function that used to be a dedicated box — a firewall, a router, a core element — and run it as a virtual machine (or set of VMs) on standard servers, and you've got a VNF. It's the concrete instance of the idea that NFV promotes at the architecture level.
The practical payoffs are familiar from any virtualization story: you scale by spinning up more instances, you place functions where capacity is, and you upgrade software without truck rolls. The term is most associated with VM-based deployments; the container-native equivalent is usually called a CNF (Cloud-native Network Function), which packages the function as microservices on Kubernetes rather than full VMs. A VNF is managed by a VNF Manager within the broader NFV MANO framework, which handles its instantiation and lifecycle on the virtual infrastructure.
Frequently asked questions
- What is the difference between a VNF and a CNF?
- A VNF runs as one or more virtual machines on a hypervisor — it virtualizes a network function but still carries a full guest OS per VM. A CNF (Cloud-native Network Function) packages the same kind of function as containers/microservices orchestrated by Kubernetes, which is lighter weight, faster to scale, and fits cloud-native operations better. Modern 5G cores lean toward CNFs; VNF is the earlier VM-based generation.
Related terms
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