SAN FRANCISCO - There are four different ways to implement cloud desktops, although you might only think of it as one delivery model.
Each way of doing desktop as a service (DaaS) is different, with its own set of pros and cons. For most shops, the best option is about use case, but sometimes it comes down to licensing.
You can host Windows client operating system (OS)-based desktops (e.g. Windows 7 or 8), Windows Server desktops (e.g. Windows Server 2008 or 2012), session-based desktops and published apps. All are considered DaaS, according to VMware's Danny Allan -- who came to the company after its Desktone acquisition --during a session about the top DaaS myths at VMworld 2014 here.
Cloud desktop OSes, sessions and apps
With Windows client-based desktops in the cloud -- essentially VDI hosted on a cloud provider's servers -- you must bring your own Virtual Desktop Access (VDA) licenses. There's no Services Provider License Agreement (SPLA) for Windows 7 and 8, so your DaaS provider cannot provide VDA licenses for you. That doesn't mean you can't host true Windows 7 cloud desktops, but it's going to cost more and take a little more planning.
Remember with VDA, you don't license the OS, you license the device used to access that OS. This means your DaaS provider still has to allocate hardware to each user, just like you would if you did VDI on premises.
There is an SPLA for Windows Server operating systems so, the DaaS provider can include the price of the licenses to use a Windows Server-based desktop in the cloud.
Microsoft does not recommend using Server OSes for your cloud desktops, however. The Server OSes sometimes have application compatibility issues, and developers may not write applications for the OS if they're more familiar with Windows 7 or 8, for example. The patching schedule for a Server OS is also different than for a client OS.
With session-based desktops and published applications, you get better density, but users share resources. If you don't need persistent desktops, session-based DaaS makes sense. But users can't install their own applications because you can't grant all the users sharing the same session individual admin rights without adversely affecting all of their desktops. If users just need access to one or a few applications, then going the published app route would be the right way to do DaaS in your organization.
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