What is the function of a virtual switch in a VDI Infrastructure ?

The functionality of a virtual switch is quite similar to that of an Ethernet switch, with added security controls provided specifically for virtual environments. Its role is to connect different segments of a network, but it differs from a hub in that it does not broadcast data packets across all ports. Instead, it filters and forwards selective data traffic based on the media access control (MAC) addresses, decreasing the overall network response time. 

 In this article we will explain the features offered by a Hyper-V virtual switch and explain use cases where a Hyper-V virtual switch is used. 

Hyper-V Virtual Switch Definition

Virtual switchIn a virtualized environment, the network layer is abstracted just like the computer and storage layer. A virtual switch connects virtual machines (VMs) with both virtual and physical networks. This allows virtual machines to exchange data traffic between one another as well as with the organization’s intranet and the internet.

In a Hyper-V infrastructure, a Hyper-V virtual switch is basically the software counterpart for an Ethernet network switch. It is available by default in the Hyper-V Manager in a Hyper-V host. It provides powerful security features to isolate network segments and inspect and control data traffic. Being software-based, a Hyper-V switch is highly configurable, and its features can be extended through plugins called Virtual Switch Extensions, allowing third-party vendors to add to its functionality and enhance its security features and networking capabilities. A Hyper-V virtual switch can enable you to enforce your organization’s security policy and ensure adherence to service-level agreements (SLAs).

Hyper-V Virtual Switch Functionality

Here are a few features of a virtual switch that can enhance the security of the Hyper-V environment:

There are several other benefits of a Hyper-V virtual switch, such as specifying minimum reserved bandwidth, capping maximum bandwidth for a VM, convenient traffic monitoring, and Explicit Congestion Notification (ECN) marking, used for notifying administrators before the switch’s buffer resources are consumed entirely.

The biggest benefit is that, unlike physical switches, a Hyper-V virtual switch can be configured and managed programmatically. Its functionality and security features can also be extended through additional plugins, using the Network Device Interface Specification (NDIS) filters and Windows Filtering Platform (WFP).

Virtual Switch Types

The Hyper-V virtual switch can be configured to operate in three different modes:

Both private and internal switch modes are used strictly to isolate traffic. The traffic never leaves the virtual switch unless a router or a routing mechanism is in place. The virtual adapters cannot connect directly with adapters on other VMs; therefore, an external virtual switch connects with the physical adapter on the host machine to connect with the external physical network.

Hyper-V Virtual Switch Use Cases

Developers can implement management packages for querying the configuration settings, capabilities and other network statistics for different ports for the Hyper-V virtual switch by using Windows Management Instrumentation (WMI). This allows network administrators to quickly glance at displayed statistics so they can stay updated on the state of the virtual switch.  

Using a Hyper-V virtual switch, network administrators can programmatically allocate resources to VMs and track bandwidth usage and VMs that are assigned Virtual Machine Queue (VMQ) or input/output virtualization (IOV) channels. A Hyper-V switch allows for resource tracking—monitoring the resources assigned to each VM as well as the resources currently in use. This functionality can be useful for hosting companies that offer different packages based on the required network performance.  

Another use case involves security. Organizations often install extensions to the Hyper-V hosts for added security. The order of these extensions may change when updates are installed. But the Hyper-V virtual switch allows the administrators to run a script for restoring the original order after upgrading.  

An organization may utilize an extension for implementing networking policies, including VLAN ID management. In such a scenario, the Hyper-V virtual switch will hand over the task of VLAN management to the extension program. The program can use the WMI application programming interface (API) to turn on transparency, and the Hyper-V virtual switch will let the VLAN tags pass. 

Managing VM’s Through Parallels RAS

Parallels® Remote Application Server (RAS) helps IT administrators manage VMs running on different hypervisors, including Microsoft Hyper-V and VMware ESXi, all under a single infrastructure. By doing so, Parallels RAS provides the flexibility required for leveraging the combined benefits of several hyperconverged infrastructure providers.

With Parallels RAS, administrators can deploy and manage a large pool of VMs easily. Administrators can utilize customized templates to deploy several guest VMs on the go. Administrators can monitor and manage all current VDI sessions through a desktop-based console as well as a web-based console.

Easily deploy and manage as many VMs as you wish on your preferred hypervisors with the 30-day free trial of Parallels RAS.