Virtual Desktop Infrastructure (VDI) is a system of virtual machines that are run on a central server and deployed on demand. It enables a rich desktop experience for the end users through a central, virtualized server that hosts the virtual machines (VMs). VDI makes use of software known as a hypervisor. A hypervisor is simply a virtual machine monitor (VMM) – it creates and runs virtual machines.
These virtual machines can be accessed from any device or location. Connection to the virtual machines happens through a software based gateway or broker that serves as an intermediary between server and end user. All processing happens on the host server, therefore the end user can harness the power of the server with minimal hardware requirements.
Types of VDI Deployment
Persistent or Stateful VDI allows a user to customize a Virtual Desktop (VD) according to their own personal preferences. The user can access this same VD each time they log in without losing any previous saved data or configurations. This provides an experience similar to logging into their own computer each time. These settings persist each time a user logs in as the data is saved for the user’s unique login credentials.
Persistent VDI requires more resources and management of those resources. If you are hosting virtual machines for a consistent base of clients, persistent VDI can be a viable option. The familiar user experience achieved through Persistent VDI can improve user satisfaction and productivity.
Non-persistent VDI is anonymous and random. All the virtual desktops reside in a central pool. When a user logs in, a random virtual machine is assigned. Each virtual machine is generic and not changes made during a session are saved. Non-persistent VDI is easier to manage, requires less storage, and is more secure as users can not make any configurations.
Virtual desktop infrastructure (VDI) use cases
Remote work – with the ever increasing remote work model, VDI allows employees easy access to the corporate network.
Shift work – in an environment where dedicated computer stations are not required, VDI allows for ad hoc connectivity as and when needed.
Call Centers are perfect for a VDI implementation, allowing users to hot desk while still being able to log in to a familiar desktop.
Educational Institutions – much like a call center – learners will have access to resources without needing a dedicated workstation. Security and restrictions can be easily applied across the board and all user experiences will be the same.
BYOD deployments can be secured by having the desktop within a secure virtual machine. Graphic Intensive applications can be performed with lower end hardware as all the processing happens on the server.
How does virtual desktop infrastructure (VDI) work?
Desktop Virtualization creates a virtual workstation, allowing users to connect from any device anywhere. This creates a clear separation between the desktop environment and all the applications that are run on it from the client machine. Desktop virtualization allows for a more secure environment that is easier to manage.
By keeping all data centrally on the server, risks of data being intercepted on other devices is reduced. The end user’s computer does not require the same high specs and all processing happens on the server, this translates into a cost saving for the company.
Components of VDI
Virtual Desktop Infrastructure consists of four main components.
- – The client that wishes to connect to the virtual machines (VM).
- – A broker acts as an intermediary that directs traffic between the client and the servers. It handles user authentication and authorization.
- – The virtualization server that hosts the actual virtual machines.
- – The virtual machines allowing the users to access the remote desktop to perform the required tasks.
Some common characteristics of VDI:
Centralization: VDI revolves around a centralized server on which virtual machines are created and made available.
OS Image: a binary image of the operating system is included in VD.
Hosting: Each virtual desktop is managed by the host and multiple instances are stored and used simultaneously.
Constant Connectivity: VDI requires a constant connection to the central server to work.
VDI Broker: The connection broker directs clients to available resources.
Hypervisor: The virtual machine monitor or vmm is the software that creates the virtual machine instances and runs them. It makes it possible for the host computer to support the multiple guest virtual machines by managing and sharing available resources.
How to implement VDI?
- Determine the required scope for your organization. Determine if you want to use VDI to replace your entire traditional setup or if you want to use VDI to make certain apps available virtually. You can make use of cloud based desktop-as-a-service solution such as Amazon workspaces or virtual desktop hardware clients.
These services do incur a cost but it does reduce initial capital expenditure. For capacity planning you need to consider how many people might connect to your service concurrently. You need to ensure that your internet and network infrastructure is up for the task.
- Choosing a VDI vendor to supply your connection broker. The broker is responsible for directing connecting clients to available resources on the remote server. Two of the most popular vendors include VMware’s Horizon and Citrix’s Virtual Apps and Desktops. Other companies like Amazon and Microsoft have joined the market providing powerful data centers in their products Workspaces and Azure respectively. These data centers provide for both your broker and the hypervisor requirements.
- If you opt for a cloud service provider, most of the setup will be taken care of for you and you will be limited to the technology dictated by the provider. For on-site solutions select a hypervisor best suited for your organization’s needs. Some common options in the market include vShpere, Hyper-V, KVM, XenServer and RHEV. All of these VDI products are fully compatible with traditional hypervisors.
- Implement and review your security. Cost saving should not be a consideration when implementing security. Make sure you use two-factor authentication (2FA or multifactor authentication (MFA) should be a minimum requirement. Usernames and passwords are not sufficient. Make use of traditional internet security in the form of firewalls and anti-malware software.
- Once everything is in place, you’re ready to piece it all together. If you are using on-site servers, make sure your VPN tunnels are set up and configured. Dedicated VPN firewalls will result in better performance for your users. Measure and review your setup continuously for connectivity and load so you can scale your capacity as required.
- Let your end users download and install the VDI client.
Benefits of VDI technology
Easier IT management – The centralized nature of VDI means that your team only needs to maintain one central machine. Software updates and security patches only need to be done once. The VDI administrators have 24/7 access to their servers and it’s not necessary to get access to the end user devices. There is no risk around losing data on the end user’s device, as everything happens on the server. New installations for new employees are easy to deploy.
Financial savings – if a company opts for on-site data centers, the costs of additional storage and connectivity enhancement may be higher initially. Opting the cloud route can be more cost-effective. Most companies allow you to pay for what you use. A cloud based VDI implementation also means not having to maintain the infrastructure yourself. Should companies provide their workforce with devices, they don’t need high end devices – resulting in cost savings.
Agility – The business can adapt to their changing needs by creating new VMs quickly. Whether providing resources for additional contractors or seasonal workers, this flexibility together with BOYD allows the company to cater for various remote working models.
Improved remote working – Allowing your workforce full access to any and all applications wherever they are aligns with the recent changes in working remotely that has become more popular and continues to grow more popular.
Drawbacks of VDI
If deployed internally, you require a dedicated team to manage and administer the system. The initial hardware procurement can be costly and the VDI team needs to ensure that all applications that are to be made available on the server are licensed and installed in compliance with the business requirements. Software and security updates become an ongoing and time intensive task.
VDI vs. DaaS
DaaS or Desktop as a Service is a cloud based service that provides virtual desktops remotely. The service provider is responsible for all the management of the infrastructure and resources, including security, maintenance and updates as well as data backups. This service comes at a cost usually in the form of a subscription fee. Like VDI, persistent or non persistent desktops are available.
The main difference between VDI and Daas is that VDI is traditionally managed internally with on site data centers. VDI deployments are generally for a single tenant – i.e. the resources are for one particular organization. DaaS on the other hand serves multiple tenants with data centers shared across multiple organizations.
VDI vs. RDS
Remote Desktop Services (RDS) is a component of Windows Server 2008 that allows machines to connect remotely and virtually. RDS is different to VDI as it has one single environment that can be accessed by multiple people. With VDI, each client has a dedicated desktop that they connect to.
The Future of VDI
With the continual adoption of BYOD and a remote working model, the need for VDI is on the rise. Allied Market Research is predicting growth to exceed $10 million by 2023. This is from a $3.6 million valuation in 2016, an increase of over 170%.
More and more companies are embracing the cloud in all business endeavors. With this change, DaaS and VDI make sense. This technology allows for seamless work-home hybrid workplaces.
While VDI has been in existence for over a decade, its future is still bright – with a move from on site data centers to cloud based ones. Companies that have been in the game for a long time are constantly upgrading and improving their offering to meet the ever changing needs of the market.