The TCP implementation within Citrix HDX/ICA protocol used by XenDesktop and XenApp and also Citrix Netscaler is pretty Vanilla to the original TCP/IP standards and definition and the out-of-the-box configuration usually does a good job on LAN. However, for WAN scenarios particularly with higher latencies and certain kinds of data (file transfers), Citrix deployments can benefit greatly from some tuning.
Citrix HDX TCP is not optimized for many WAN scenarios but at the moment it can also be tuned manually following this advice: CTX125027 – How to Optimize HDX Bandwidth Over High Latency Connections. This is one configuration I’d love to see Citrix automate as having to tune and configure the receiver is fiddly and also not possible in organisations/scenarios where the end-points and server/network infrastructure might be provided by different teams or even companies (e.g. IaaS).
For Citrix NVIDIA GRID vGPU customers with looking at high network latency scenarios – it really is worth investigating the potential and benefits of TCP window tuning. I’d be really interested to hear feedback if you have tried this and what your experience / thoughts are too!
Norwegian, Marius Sandbu was recently awarded NGCA status by NVIDIA for his work with our community through his Netscaler, remoting protocols and experience with technologies such as UDP and TCP/IP. You can follow him on twitter @msandbu and of course do follow his excellent blog on http://msandbu.org/ !!!
Update (16th Aug 2015) – Now a CTX: CTX201802 – FAQ: HDX Extra Color Compression (ECC) Policy in XenApp and XenDesktop
Extra Color Compression (ECC) is a policy that can be applied to control how HDX manages bandwidth vs. quality and other resources (e.g. CPU). It is documented in the XenDesktop and XenApp product documentation here.
A while back I wrote an article: “12 Monitoring Products for Citrix XenServer – including options for hybrid infrastructure and mobile, XenDesktop, Cloud, iPad”, since then I’ve moved into working in Product Management for HDX, providing the graphics technologies for Citrix XenDesktop and XenApp. I’ve had numerous requests for a similar list of monitoring options for HDX within a Citrix XenApp or XenDesktop environment. Many of those applications, which I suggested for XenServer are also appropriate, but there are also many products available which are particularly tailored to the needs of a XenDesktop or XenApp user.
A few months ago I took over as Product Manager for the Linux and Android Receivers as well as retaining the roadmap for HDX Graphics.
Some weeks back I went through my first release of the Linux Receiver with the 13.2 release. So I thought I’d highlight what’s new, ask for feedback on where we are and also ask what you’d like to see in future releases.