Hyper-V Network Virtualization and Virtual Switch
Hyper-V Network Virtualization provides “virtual networks” to virtual machines similar to how server virtualization (hypervisor) provides “virtual machines” to the operating system. Network virtualization decouples virtual networks from the physical network infrastructure and removes the constraints of VLAN and hierarchical IP address assignment from virtual machine provisioning. This flexibility makes it easy for customers to move to IaaS clouds and efficient for hosters and datacenter administrators to manage their infrastructure, while maintaining the necessary multi-tenant isolation, security requirements, and supporting overlapping Virtual Machine IP addresses.
The Hyper-V Virtual Switch is a software-based layer-2 network switch that is available in Hyper-V Manager when you install the Hyper-V server role. The switch includes programmatically managed and extensible capabilities to connect virtual machines to both virtual networks and the physical network. In addition, Hyper-V Virtual Switch provides policy enforcement for security, isolation, and service levels.