Q: How are presentation virtualization and desktop virtualization different?

A: Presentation virtualization products let you install an application to a server. Once it's installed, that application can be used by multiple, simultaneous users on that server. Users connect to the server using individual sessions, preserving user separation. With presentation virtualization, application processing is abstracted from the delivery of that application's graphics and I/O.

This consolidation of many users onto a single server is very different from the approach used by desktop virtualization. Unlike the many-to-one approach used by presentation virtualization, desktop virtualization uses a one-to-one linkage between users and the OS instances they connect to.

These two approaches can be confused because of the protocol used to connect user to computer. In products such as Microsoft Remote Desktop Services (RDS) or Citrix XenApp, the same protocol is used for both approaches, with RDS using the RDP protocol and XenApp using the ICA protocol.