Key VDI network requirements and considerations
One of the prevailing challenges in Higher Ed over the past decade or so has been enabling remote access to campus computing environments and resources. This has been amplified by COVID-19. This challenge has seen several virtualization solutions enter the market, none more popular than VDI (Virtual Desktop Infrastructure).
The ability of VDI to enable anytime, anywhere access to a fully configured and managed Windows desktop is a winning solution and is popular with medium to large institutions who can justify the cost. The solution still has merit today even with cloud-based solutions taking center stage but there are several considerations to take into account when designing a VDI deployment. One of the foundational layers that must be designed properly is the VDI network.
- Needs of the organization
- Needs of users
- Resources required by users
- Existing network and bandwidth capacity and capabilities
- How much bandwidth is already being used
When designing a Desktop Virtualization network, there are 3 basic aspects to consider: internal throughput, external throughput, and latency. These considerations will ensure that the VDI solution is fit for purpose and provides users with the access they need when they need it. Ensuring the correct network requirements during implementation will make sure the VDI is able to function properly and meet users’ needs.
For internal throughput, bigger is better. Implementing a 10Gbs, 20Gbs, or even 40Gbs core network in the data center will ensure excellent performance during the operations with the highest demand, such as recomposing pools, boot storms, and login storms.
External throughput is required for all the connections from endpoints to the VDI desktops. These might be computer labs, teaching podiums, and off-campus BYO devices. For all campus endpoints, a minimum of 1GB/s should be the baseline. For off-campus, the more throughput the better. This might mean redundant and paired internet pipes to the datacenter and upgraded firewall and router appliances to handle the extra data. Either way, it's important to meet the bandwidth requirements of delivering to any given number of devices.
Finally, latency is the enemy of VDI. Designing and provisioning network hardware with low latency specs will ensure an acceptable user experience, especially for workloads that require high fidelity such as music editing, CAD/CAM software, or animation projects.
- Test – emulate the network conditions of a VDI set up to understand what impact the solution could have on the network
- Assess latency and capacity problems to make necessary changes to the network
- Calculate current network usage
- Factor in future growth of network
With any network design project, key activities should include testing, monitoring, and tuning. These activities are even more critical for a VDI deployment as network performance has a huge impact on the success and usefulness of VDI. As noted above, throughput and latency are critical factors to monitor and load test. In addition, capacity and future growth should also be considered so that institutions don’t build themselves into a corner with no room to expand.
- Always-on connectivity and network resilience
- Latency – look into network performance and peaks in usage to determine the maximum load of the network
- Scalability – can the solution be scaled up or down accordingly?
For many institutions that made a large investment in VDI, the platform became the only source of computing on campus. Thus, VDI would need to be categorized as mission-critical to teaching and learning, and have the necessary protections to stay running. Systems and processes to facilitate disaster recovery and business continuity (DR/BC) need to be included with any wide-scale VDI deployment. Further, network scalability and security also need to be addressed to ensure continuity of service during internal or external network-based events or attacks.
At the end of the day, VDI as a computing service has its place on campus in Higher Ed but careful planning and design is needed to ensure a well-performing solution. At the foundation will always be the network and as we’ve shown there are many aspects to consider.
Some useful & related reading...
What kind of storage does VDI need, and how much of it?
What are the key differences between Citrix VDI and VMware VDI?
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