The benefits of hosting virtual desktops in the cloud compared to building out an on-premises VDI environment seem...
to outweigh the general distrust of public cloud.
Cloud services give companies a way to eliminate the burden of managing data center infrastructure -- all that nasty hardware and administration, patching, upgrades and purchasing new equipment. But there are several reasons IT pros resist public cloud services. Specifically:
1. The outage Amazon experienced in April 2011 that left customers without access to their data for several days. There were lots of unhappy campers there -- Service Level Agreement (SLA) or no SLA. Even one failure can affect many customers, especially when all their eggs are in one basket.
2. Putting mission-critical applications in the cloud means giving administrators you can't even see access to sensitive corporate data -- and trusting them with it.
3. If you want to move something to the cloud, you can't just stick it there. It has to be in a particular format. What happens when you want to port the application back to your data center? Some say it might be more expensive to get out of the cloud than to get into it.
In spite of these and other negatives surrounding public cloud, there is one bright spot shining in the darkness -- Desktop as a Service (DaaS). Cloud-based virtual desktops cut the costs and complexity surrounding virtual desktop infrastructure (VDI).
Putting the desktop in the cloud has some benefits that do not apply to server hosting. For example, servers are tied to storage and other data and application sources, making it difficult to move or reconfigure. Desktops don't have that issue.
Also, end users access their desktops on laptops and other devices from home, hotels, coffee shops and airports -- making it difficult to control and secure them. Desktop in the cloud allows full control by the IT staff; if the laptop is lost or stolen, the virtual desktop can be killed and the thieves get nothing. (This is also the case with VDI.)
In addition, when a user's laptop dies, they can't be productive during the time it takes to restore the data. With a cloud-based desktop (and with VDI), restoration is much faster.
Clearly, VDI and cloud-hosted virtual desktops deliver similar benefits. Let's dig in to DaaS to see the benefits over server-hosted VDI.
VDI vs. DaaS
VDI software gives IT a way to host desktop images in their own data center and present those images to remote end users over a network. The idea is to provide central management and control for provisioning, updating, patching, controlling software and providing computing resources.
Because Desktop as a Service is the latest buzzword, a number of vendors claim their product is DaaS or delivers DaaS. So, what is DaaS and how does it differ from VDI?
What is DaaS?
DaaS is the outsourcing of VDI to a third-party service provider. Typically, DaaS has a multi-tenancy architecture and the service is purchased on a subscription basis.
In this delivery model, the service provider manages the back-end responsibilities of data storage, backup, security and upgrades. The customer's personal data is copied to and from the virtual desktop during logon/logoff and access to the desktop is device, location and network independent.
The terms DaaS and Desktop as a Service are actually copyrighted by Desktone, Inc., a company that produced the first DaaS product in 2008. The company claims that DaaS provides all of the benefits of VDI without any of the upfront infrastructure costs. DaaS customers can rapidly provision desktops to users on any device, anywhere. The service starts at $30 per month, per desktop.
Though DaaS desktops run in a remote data center, the desktops are connected to your corporate IT environment through a private network connection. Access to the desktops is based on your existing Active Directory.
While I am still not a big fan of the public cloud for data center services, pushing the desktop to the cloud makes a lot of sense.
The list of negatives about public cloud services is somewhat reduced when applied to DaaS. While an outage such as Amazon's earlier this year would have an equally negative effect on cloud-based desktops, the benefits of speed and flexibility for deployment, along with relatively little risk, would still make the cloud desktop very attractive.
Imagine a college campus that has to re-provision scores of computer labs every semester. Simply providing cloud-based desktops with virtually unlimited capacity and configuration options makes a lot of sense.
ABOUT THE AUTHOR:
Gary Olsen is a solution architect in Hewlett-Packard's Technology Services organization and lives in Roswell, Ga. He has worked in the IT industry since 1981 and holds an M.S. in computer-aided manufacturing from Brigham Young University. Olsen has authored numerous technical articles for TechTarget, Redmond Magazine and TechNetmagazine, and he has presented numerous times at the HP Technology Forum. He is a Microsoft MVP for Directory Services and is the founder and president of the Atlanta Active Directory Users Group.