VDI network management guide

Desktop administrators may love the benefits of VDI, but data center network managers might not be so ecstatic.

Virtual desktop infrastructure (VDI) adds a significant load to your network, and throughput could suffer. You want to make sure you have enough bandwidth to accommodate virtual desktop connections, while at the same time ensuring low latency.

Sound a little tricky? It sure is.

It's also challenging to deliver graphics-heavy applications over the network. You'll need acceleration technology to get the best performance from wide area networks (WANs). Overcome these challenges with the resources in this VDI network management guide.

Preparing your network for VDI

What factors affect VDI network performance?
Monitor network activity before deploying VDI to determine load peaks and valleys. Boot storms, when many virtual desktops launch at one time, can have a major effect on VDI network performance.

Also consider whether you're using connected or disconnected VDI. With connected VDI, network segmentation and Quality of Service controls can help reduce traffic between the endpoint and the host. With disconnected VDI, the virtual hard drive is stored and executed on the physical endpoint device. This offline VDI, however, makes it difficult for IT to control access and provide support for business applications.

Ensuring network resilience and redundancy
For an efficient VDI network, you need fault tolerance. Make sure that the network is reliable and doesn't drop packets -- even if a network card, switch or server fails. The best ways to achieve VDI network fault tolerance are by creating redundancy among physical network components and consistently monitoring performance.

How VDI can improve network security and performance
It's pretty easy for hackers to get into your office network through penetration-test drop boxes or wireless access points, but VDI can strengthen those weak points. When accessing corporate data from a virtual desktop, a user is connecting to the data center network rather than an office LAN or Wi-Fi. Internet gateways, firewalling, access control and greater physical security make the data center network more secure.

VDI network management challenges

The problem with bandwidth and VDI
One of the main challenges of VDI network management is ensuring that you have enough bandwidth. Sometimes technologies such as Voice over Internet Protocol or video conferencing have to share bandwidth with virtual desktops, putting a strain on performance. To manage bandwidth in a VDI environment, you can use optimization tools that prioritize traffic, reduce latency and provide Quality of Service.

Five remote desktop connectivity problems
If a user loses virtual desktop connectivity, it's often because of a network failure. If that's the case, try using the command line to test connectivity to the host server and connection broker. Other pitfalls include overwhelmed VDI network capacity and authentication issues. Remote Desktop Services requires network-level authentication before a user can connect, for instance, but not all clients support that authentication.

Using content redirection to run rich media
Delivering graphics-intensive applications to virtual desktops can be difficult. It takes a lot of bandwidth to transmit 3-D or video apps via a remote display protocol. These protocols have improved over the years, but they don't always provide the best app performance. Instead of straining your network with media-rich apps, consider tools that offer content redirection.

Delivering virtual desktops over the WAN

Improving the remote experience with WAN acceleration
Delivering virtual desktops over a WAN is notoriously difficult because the connection tends to be slow. Luckily, you can use WAN acceleration technology to improve the remote user experience. WAN accelerators compress network packets, optimize bandwidth usage and can even monitor and report traffic activity.

Boosting WAN performance with software-only tools
Aside from WAN acceleration hardware appliances, there are also software-only accelerators available for remote protocol display optimization. Ericom Blaze, for example, is a standalone software accelerator for Microsoft's Remote Desktop Protocol (RDP). Quest Software's vWorkspace product (now owned by Dell) also offers RDP optimization with its Experience Optimization Protocol feature.

How display protocols affect WAN performance
Different remote display protocols provide different performance levels when delivering virtual desktops over the WAN. Microsoft's RDP, for example, doesn't work as well with high-latency connections and video updates. Citrix updated its Independent Computing Architecture protocol to provide better support over the WAN, but both protocols could still benefit from third-party WAN acceleration tools. VMware's PC over IP, on the other hand, has built-in technology to reduce latency.

When do you need a WAN?
Unless you absolutely need a WAN, it's probably easiest to run desktops or applications directly on a client device. For some organizations, however, security or user needs require them to connect to a data center WAN. If that's the case, try out different applications and monitor how they perform over the network. Improving WAN performance could just be a matter of lowering app resolution or addressing packet loss.