Welcome to Part 2 of our discussion about hosted desktops. In Part 1 we looked at what a hosted desktop is, and the differences between Session Virtualisation and Full Virtual Desktops.

In this part we will look at the impact of the protocol on end user performance.In our work to provide high performance Hosted Desktops we have found a number of key areas for comparison, all of which make a huge difference to end user experience.

Each vendor supports the traditional Microsoft Remote Desktop Protocol, but has also developed improved protocols.

Protocols

The hosted desktop protocol is used to transmit the screen information to the user, and also provide keyboard, mouse and other device connectivity (e.g. USB, printers, etc…).

Remote Desktop Protocol (RDP) has been used by Server Administrators and Terminal Services users for many years. It handles basic text and windows well, but doesn’t perform at all well with graphical applications or over lower speed internet lines (3G, home broadband, etc…).

Each vendor has chosen (and in many cases developed) a high quality protocol to provide both improved bandwidth usage and much better graphics delivery across these lower speed links.

VMware utilises PC over IP (PCoIP) and Citrix uses HDX. Both of these protocols provide high definition graphics as well as the usual text and windows drawing functions. These protocols use various bandwidth control methods, and deliver good graphics performance across lower speed internet lines (including 3G/4G and home broadband).

More recently Microsoft has also developed RemoteFX which in its latest release now also provides improved bandwidth usage and better graphics.

As well as VMware, Citirix and Microsoft, a number of other parties have developed similar protocols, some of which also deliver the performance and high quality graphics discussed above.

Each of the higher quality protocol can be optimised in a different way, but all deliver largely the same features.

These higher quality protocols are critical to delivering a quality end-user experience, and although many parties across the industry prefer one or other protocol, the important factor for end-user performance is to ensure that one of the high quality protocols is used (rather than traditional RDP).