As the dust settles on VMware’s VMWorld End User Computing group’s re-invigoration, it is entertaining to wax lyrical on how users will be wedded with their data in the glorious shining summer of a post-PC era. But, we still stand in the cold, blustery autumnal now of mixed desktop environments and legacy applications. Organisations will rely on applications requiring a Microsoft OS for a good few years yet. However, we’ve already begun the transition from a truly distributed environment from individualised, personal computers. The delivery of applications (and desktops) regardless of device type has been available to organisations since the 1990s with Citrix being one of the first to deliver the next generation of applications and desktops to the previous generation of devices and operating environments.

XenApp 6.5 is Citrix’s latest offering of their renowned Presentation Virtualisation (PV) service. Citrix are not alone in updating their feature set. Earlier in 2011 Microsoft introduced SP1 for 2008 enhancing the OS for the core Remote Desktop Services’ (RDS) session virtualization service, Ericom released PowerTerm WebConnect 5.7.1, ProPalms updated TSE to 6.5 and Quest announced vWorkspace 7.2 MR1.

Yet, the majority of virtual desktop instances are delivered using Citrix’s XenApp  (including previous releases Presentation Server and MetaFrame). VMware’s VDI may have sparked a flurry of clones, but PV’s greater user density capability requires less complex architecture and offers easier management: and Citrix was there first. PV is a reliable choice for many heading-towards-post-PC thin-client and remote access/BYOC deployments. XenDesktop may be Citrix’s pin-up de jour, but XenApp is still a major force in terms of revenue generation and has an extensive customer base. In terms of PV and desktop virtualisation scale, XenApp provides the yardstick.

What’s new XenApp 6.5? Is the new release simply a fancy fanfare for a little gloss and a new management console name? Is it possible that there are new tricks for Citrix’s faithful companion. Does XenApp 6.5 demonstrate that Citrix are still at the fore-front of desktop virtualisation innovation?

XenApp: More than just Application Delivery

XenApp has long been recognized as the de-facto standard in on-demand app delivery. Whether XenApp is included as a component of XenDesktop Enterprise or Platinum editions or most likely, deployed as a standalone product, Citrix’s Microsoft RDS enhancement offers organisations a range of features to deliver application or desktop virtualisation.

Unlike VMware’s View – XenApp can be a solution to deliver desktops or applications remotely. It can be a solution to offer access to a specific application, or a range of applications – or entire desktops. As such it can be incorporated into solutions that utilise existing traditional PCs but deliver to other devices – such as tablets, smart phones or thin-clients. XenApp services can be readily and securely delivered over the Internet delivering collaboration, branch/remote access or home working services.  XenApp can be virtualised, but doesn’have to be. This can reduce complexity in some environments. As with any virtualisation solution that delivers a Microsoft based environment, it does have a Microsoft license requirement – but the cost of RDS Client Access License is less than a Windows Virtual Desktop Access: important for thin-client, or tablet deployments.

As such XenApp is often utilised for solutions beyond services for task-based workers:  previous releases have often been pushed to the limits of what organisations can achieve, and what users can bear. With this latest release, how have Citrix continued to attempt to justify the hefty price tag of XenApp Enterprise or Platinum edition licenses?

What are the New Features in XenApp 6.5?

So, what does your organisation get for its half of a full point revision of XenApp?

  • Instant Application Access How soon is now?  XenApp 6.5 has a collection of features intended to improve the user experience by eliminating delays when launching and maintaining sessions. By using configurable Session Prelaunch policy settings, a session can be started automatically when a user logs on to the farm. The Session Linger features allows sessions remain active for a configurable period before termination, rather than terminating when user closes their applications. Finally, the zero-configuration Fast Reconnect feature minimizes the delay when users reconnect to existing sessions.  XenApp farms can provide both full desktop sessions, and applications to desktops (physical and virtual). These app access services will help further blur the lines between application and desktop services so the end-user is less aware of where services are hosted, and spend less time waiting for applications to start. While this will improve user productivity and offer different delivery options, bear in mind that these features can consume licenses: so the improved speed will incur an increase in license use. For many, there is a useful simplicity and cost saving in the concurrent user XenApp license model: these features mean that model is no longer so exact.
  • Multi-Stream ICA Citrix’s Independent Computer Architecture (ICA) protocol has been a key factor in helping Citrix be the PV market leader. While there are many discussions on which remoting protocol is “the best”, ICA has a reputation for delivering applications over a wide range of networks. That said, key challenges of such architectures are network latency and performance as we’ve discussed before. In XenApp 6.5 administrators are able to deliver ICA traffic over up to four TCP/IP streams: enabling more granular control for Quality of Service (QoS) routing.  Now, rather than raise the priority of  all of the channels in ICA, customers can provide superior audio/visual quality for apps without disrupting other network traffic such as HTTP or SMB. However, this is a new technology so bear in mind not all non-Citrix network devices will support it in all instances: at present, Secure Sockets Layer (SSL) connections are only supported when the connections are traversing a Citrix Access Gateway that supports multi-stream. Still, this brings a valuable option in optimising bandwidth use.
  • Enhanced Desktop Experience  It’s generous to moniker this previous XenApp 6.0 add-on a “new feature”, but its definitely not a bug. Many user’s rarely care about the core OS: but they’d rather their thin-client workspace was like their work or home PC. An issue here is a default Windows 2008R2 desktop isn’t very Windows 7. This feature of XenApp 6.5  enables support for themes, installs accessory apps, and allows for the display of high-res wallpapers as well as provide a Windows-7 like Start Menu and taskbar. In addition, there  the majority of the HDX enhancements introduced by XenDesktop 5.5 are also applicable for XenApp 6.5: helping to reduce the deviation of XenApp’s multi-media experience that would have many considering XenDesktop or deploying traditional PCs.
  • Improved Printing Performance Again, a previous add-on pack for XenApp 6.0 has been folded into a complete release.  This means XenApp 6.5’s printing features include improved print session performance, lower bandwidth required for printing (Citrix quote up to 90%), and an improved user experience when printing to redirected client printers. Despite the rise in tablets and e-readers, the paperless office is still largely a paper moon: printing performance – especially for remote/branch offices can be a major headache for  thin client migrations if it isn’t accommodated appropriately.
  • Desktop Director XenDeskop 5 introduced Desktop Director. The web-based console can help desk support staff by giving the capability to assist users with applications delivered by XenApp and with desktops delivered by XenDesktop – a first step in a long anticipated common management platform environment that has been glaringly missing from previous releases.
  • Citrix Receiver – any time/place++ ..  Citrix’s desktop virtualisation service range has strength in the breadth of devices that support and deliver ICA: helping to drive the cost of thin-client devices down and expand use cases for application and desktop delivery beyond the LAN. XenApp 6.5 takes advantage of new Citrix Receiver enhancements for the core Microsoft Windows environment and advanced Linux device support. Citrix claim they can help deliver applications to over one billion devices, PCs, Macs, tablets, smart phones, and thin clients – as well as new environments like iOS, Android, and Google ChromeOS. However, if you have legacy Presentation Server/MetaFrame environments be mindful that the latest Windows Receiver isn’t supported to be fully backwards compatible.
  • Cloud Bursting. XenApp 6.5 is only available for the Windows 2008 R2 platform and one advantage of that is both the OS and the XenApp environment is far easier to automate to enable environments to be dynamically scaled to meet demand.  As well as a number of powershell management enhancements, XenApp 6.5 deployments can be scaled in record time by creating “controller” or “worker” roles in a XenApp server farm.  Because workers in the farm need to sync much less data, fewer overall database transactions are required.  Plus, these new roles make the process of joining a large number of servers to a XenApp farm faster and easier. For th0se considering an upgrade, be mindful that XenApp 6.5 does not provide a binary upgrade path from previous versions, including XenApp 6.0 – although there is a migration tool to aid migration tasks when moving from a XenApp 6 or XenApp 5 farm.

In summary, an improved user experience; with greater automation and management. Windows 2008R2 is Microsoft’s best platform for presentation virtualization and Citrix XenApp 6.5 has features to offer organisations who want a readily manageable platform to support thin-client desktops to organisations who want to be able to dynamically provision their application and desktop virtualisation platform to best accommodate load.

What’s missing in XenApp 6.5?

You may be saddened to know that the Easy Call voice service is no longer part of XenApp. No? Fair enough.

x32 support? To be fair, the x64 OS is the better operating environment for scale and reliability although it is administratively tedious that while the users may be presented with a seamless application delivery environment there is more administrative effort if you are supporting a mix of back-end environments.

The new XenApp 6.5 does introduce more tools for automation and offers scripting functions. The management change with perhaps the biggest impact to seasoned farm administrators is that you won’t be able to run the AppCenter console (formerly Discovery Services Console (yes, Citrix changed the name again)) on any server in your farm and choose “localhost” in the discovery – you’ll have to point the console at a Controller server. Still, despite Citrix having both a hosted desktop and a session desktop solution, unlike Quest’s vWorkspace these two options are effectively managed and maintained in two different environments. While the performance enhancements help blur the boundaries for users Citrix administrators still have two quite separate environments to manage. However as the appearance of Desktop Director shows, the convergence is coming.

There is still no Universal Printer Driver option for network printers. 7 is a lucky number right?

Iron Cove Lessons

In the 1860s Iron Cove Creek was a freely flowing waterway which in places broadened into ponds that made excellent and picturesque swimming holes. Now major waterway in Oz. “All very interesting“, you say, “but why am I telling you this“?

Like its antipodian waterway namesake, XenApp 6.5 has a heritage that is rich, all be it with the occasional dead possum. Its start was fairly free flowing, it has had difficulty in organisations who struggled with the difference the centralisation of services made, who found limitations in delivering remote access solutions. Transitioning to a centralised enterprise application delivery was often hazardous to the health and the convenience of an ever growing community of users. Especially if they wanted to print. Or watch a video or deal with3D graphics. The architecture and design was prone to flooding under deluge. However, XenApp 6.5 now sits on a core OS that has had session based services designed in. This, in addition to the improved core architecture, management and user experience improvements offer a very robust, scalable solution for application and desktop delivery.

Is it better than VDI? For many, the answer will still be “yes”. XenApp 6.5’s feature list has additions that improve the scalability and performance for very large environments, but the simplicity of configuration and user experience enhancements will still appeal to medium sized organisations for delivery of desktops and applications. With XenDesktop 5.0 and XenApp 6.0 Citrix lost focus of that message, the customer choice blurred with the suggestion of an either/or offering. Quest garnered successes in highlighting that the story is not about a single technology: Quest promoted their vWorkspace as delivering a platform. With the XenApp 6.5 Citrix have tacked back and got the wind behind them with a similar message. For many organisations, PV can provide the heart of an enterprise desktop strategy, and XenApp is Citrix’s most complete PV solution. There is an argument that the cost of the concurrency licenses of Enterprise and Platinum editions is high (especially in comparison to VDI). This gives other vendors an opportunity to scupper Citrix’s market as existing estates come to review a move from x32 to x64 services, especially as to move to XenApp 6.5 farms need to be recreated. Still, a difficulty for those vendors is in positioning their own offering in terms of user experience features, scalability, ease of set-up and end-device support as well as the experience and drive of channel partners.

With this latest XenApp release, Citrix have set another high-tide mark in offering a service that can fit into your enterprise desktop delivery strategy to help you transition between the PC and What Comes Next.

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Andrew Wood (144 Posts)

Andrew is a Director of Gilwood CS Ltd, based in the North East of England, which specialises in delivering and optimising server and application virtualisation solutions. With 12 years of experience in developing architectures that deliver server based computing implementations from small-medium size business to global enterprise solutions, his role involves examining emerging technology trends, vendor strategies, development and integration issues, and management best practices.

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