NetVMs

NetVMs are virtual machines or virtual instances that are specialized to perform network processing tasks. They are commonly used to implement network functions as software, such as virtual routers, firewalls, intrusion detection systems, NAT, VPN gateways, load balancers, or packet brokers, within a broader software-defined networking (SDN) and network function virtualization (NFV) environment.

In practice, NetVMs run on standard hypervisors on commodity hardware and may be deployed as stand-alone VMs or as components within containerized platforms. To achieve high traffic throughput and low latency, they often leverage high-performance I/O stacks such as DPDK, netmap, or VPP, and may use PCIe SR-IOV NICs with direct or mediated access. Para-virtualized drivers like virtio are also common in some deployments. NetVMs are designed to be scalable and can be managed as part of VNFs or CNFs within orchestration frameworks.

Management and lifecycle of NetVMs typically involve instantiation, scaling, updating, and migration, coordinated through NFV MANO stacks or cloud/Kubernetes orchestration. Operators tune resource allocation (CPU, memory, hugepages) and network configurations to meet performance and isolation requirements. Security and reliability are addressed through VM isolation, network segmentation, and monitoring.

Use cases include data centers, cloud providers, and telecom networks where flexible, software-defined network services are needed. While NetVMs offer modularity and rapid deployment, they may incur more overhead than containerized or bare-metal implementations, and require careful planning for performance tuning and operational complexity.

See also: NFV, VNFs, CNFs, SDN, DPDK, SR-IOV.