The changing face of virtual access

Virtual access technology (see Sorting out the different layers of virtualization for more information) has been changing over the last six months from a technology that largely replicated what X-Windows did for UNIX and Linux systems to something that has the capability to better deal with the many types of data and media a person using today's systems expects.

When protocols, such as Citrix's Independent Computing Architecture (ICA) or Microsoft's Remode Display Protocol (RDP), displaying screen information and allowing users to input data using a keyboard and a mouse.These protocols were never designed to deal with the bandwidth requirements and complexities imposed by streaming media, large 3D graphics and the requirement to find, configure and then use intelligent devices a remote client system may allow.

Citrix's HDX

Citrix recently launched their version of virtual access accelleration and optimization technology under the name "Citrix HDX for XenDesktop and XenApp". Here's how the company describes it:

Citrix HDX for XenDesktop and XenApp includes a broad set of technologies designed to enable a high-definition user experience for virtual desktops and applications. HDX builds on existing technologies in the Citrix Delivery Center™ product family, extending them with new innovations for today’s media-rich user environments.

These technologies reside across the entire end-to-end delivery system. HDX in the datacenter is designed to leverage the processing power and scalability of servers to deliver advanced graphical and multimedia performance, regardless of the capabilities of the end point device. HDX on the network is designed to incorporate advanced optimization and acceleration capabilities such as the Citrix ICA® virtual delivery protocol and other third-party technologies to deliver a great user experience over any network, including high-latency, low-bandwidth environments. HDX at the device is designed to leverage the computing capacity of endpoint devices to enhance user experience in the most efficient way possible.

There are six categories of HDX technologies that work together in concert to provide the best experience for all user scenarios. Each of these six categories includes a broad range of new and existing technologies that extend throughout the Citrix Delivery Center product family.

• HDX MediaStream – Accelerates multimedia performance by sending compressed streams to endpoints and playing them locally.
• HDX RealTime – Enhances real-time communications using advanced bi-directional encoding and streaming technologies to ensure a no compromise end-user experience.
• HDX 3D – Optimizes the performance of everything from graphics-intensive 2D environments to advanced 3D geospatial applications using software and hardware based rendering in the datacenter and on the device.
• HDX Plug-n-Play – Enables simple connectivity for all local devices in a virtualized environment, including USB, multi-monitor, printers and user-installed peripherals.
• HDX Broadcast – Ensures reliable, high-performance acceleration of virtual desktops and applications over any network, including high-latency and low-bandwidth environments.
• HDX IntelliCache – Optimizes performance and network utilization for multiple users by caching bandwidth intensive data and graphics throughout the infrastructure and transparently delivering them as needed from the most efficient location.

Citrix has also designed its HDX framework to enable seamless interaction between these six areas with its innovative “adaptive orchestration” technology.

• HDX Adaptive Orchestration – Senses underlying capabilities in the datacenter, network and device, dynamically applying the best combination of Citrix HDX technologies to ensure a high-definition experience to meet each unique user scenario.

Snapshot Analysis

Provision Networks, HP and now Citrix offer technology that uses earlier protocols and technology for what they do best - deliver text and simple screen information, and adds new technology to optimize and accellerate the delivery of media, large scale graphics and allow the use of remote USB devices.

Wyse, HP and several others have also been offering technology that achieves the same ends.

What this means is that virtual access to applications running in the datacenter and, possibly, hosted in the cloud can offer performance that matches the requirements of all but the most demanding applications and users.