XenApp 6 is not only a complete rewrite of the popular XenApp 5 product for a 64-bit platform but it's been enhanced to provide greater functionality, in some cases what looks to have been simplified has involved a lot of work under the hood.
Due to it's x64 codebase, XenApp 6 is only available for Windows 2008 R2, so there's a bit of a dilemma here for those still running previous versions of Windows server, as not only is there the upgrade to the new XenApp version to consider, but a move to Windows 2008 Server R2 is also needed. This can increase the effort and resourcing required to move to this new version of Citrix's product.
XenApp AppCenter is a new management console designed to provide a single point of access to XenApp and other services within a typical farm. This console replaces the previous need to use several different consoles and kind of, goes back to the old days of using Presentation and MetaFrame server farms, where one console provide most of the control over the functionality available.
The new Citrix Receiver for Windows supports eight languages with expanded support for plug-ins including Single sign-on, WAN acceleration, App-V and Easy Call. There is a new Dazzle-enabled Receiver for Mac. And for mobile devices, users can use Receiver on iPhone, Android or Windows Mobile to access applications hosted on XenApp 6.
Several HDX improvements as part of HDX RealTime are also incorporated in XenApp 6 including new audio/video codec support (promising up to 90% less bandwidth consumption) which enables teleconferencing using VoIP soft phones as well as video conferencing using Microsoft's OCS (Office Communicator) video conferencing service.
More devices can now be connected including webcams, cameras, scanners etc, allowing more applications delivered via XenApp to be able to use these newly supported USB devices.
XenApp Scalability improvements / XenApp 6 performance improvements over previous versions are also being touted by Citrix, as a big improvement over the previous version. This has been typical of every version of the presentation server line base of products and indeed including the older MetaFrame product.
Citrix state an improvement of around 15% - 20% more users can connect per XenApp 6 server compared to XenApp 5 but critically this is based on XenApp 6 on a Windows 2008 R2 platform which XenApp 5 doesn't work with, so it's not a like for like comparison. Other performance improvements include faster logging on times for users through improvements in profile management, which has been the bane of many a Citrix, indeed Terminal Services environment for many years.
Whilst on paper this looks good, I'm always sceptical about these so called performance improvements until they've been independently tested. Simply because the way the performance aspects are tested and measured need to be fully understood and validated, otherwise it's just another bunch of statistics and we all know how statistics can be massaged to prove virtually anything you want.
XenApp Server Role Manager allows for a more simplified installation process and greater control over the components installed. It essentially reduces the likelihood of installing something that's not required, so for an enterprise XenApp farm, why would you need to install the presentation capability to a bunch of data collectors when no user is actually going to connect to these servers to access applications?
It just seems a waste of resources having to install additional functionality which isn't going to be used. In smaller farms this may not be the case where a single server could potentially service several roles but in the medium to large farms, it's vital to dedicate servers for particular roles, which allows for better scalability, resilience and management.
With this new service, just by selecting the role, only those components which facilitate that role will actually be installed, allowing for better utilisation of hardware resources on that server.
XenApp now has App-V support, allowing App-V applications to be published using XenApp. To accommodate this change, Citrix has developed a App-V plug-in for their client side Receiver. This is great for those customers who don't want to be tied into Citrix's application streaming and use Microsoft's technology instead.
Dazzle is Citrix's Self Service Application Delivery mechanism whereby users can select the applications they want to use from a storefront like interface, a bit like the way Apple iTunes allows users to select music tracks they are interested in buying. This has been enhanced to include support for Apple Mac devices and integrates Microsoft App-V application packages, providing a single storefront interface for different application types to be selected. To the user, the application on Dazzle is just and application and that's all they'll see, with the complexities of different application types cleverly masked in the XenApp product.
We will be conducting our own independent assessment of Citrix's new, which help our customers receive informed strategies and solutions for moving forward to XenApp 6.