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Virtual Network Switch
Updated: April 7, 2009
Applies To: Windows Server 2008
This is preliminary documentation and subject to change.
A virtual network switch (also referred to as a virtual switch) is a virtual version of a physical network switch. A virtual network can be configured to provide access to local or external network resources for one or more virtual machines.
When you install Hyper-V and create an external virtual network, the management operating system (sometimes called the parent partition) uses a new virtual network adapter to connect to the physical network. The network connections consist of the original network adapter and the new virtual network adapter. The original physical network adapter does not have anything bound to it.
However, the virtual network adapter has all of the standard protocols and services bound to it.
Hyper-V binds the Virtual Network Service Protocol to a physical network adapter when an external virtual network is created.
A virtual network works just like a physical network except that the switch is software based and ports can be added or removed dynamically as they are needed.
After an external virtual network is configured, all networking traffic is routed though the virtual switch. For this reason, we recommend using at least one additional physical network adapter for managing network traffic. The virtual switch functions as a physical switch would and routes networking traffic through the virtual network to its destination.
The following is a list of all aspects that are part of this managed entity: