It's approximately a year old but it's still a great video demo anyway of Brian Madden testing Citrix's ICA protocol, Microsoft's Remote Desktop Protocol and Redhat's SPICE protocol (previously by Qumranet).

It becomes obvious near the end that SPICE is very heavy on bandwidth coming from the server and ICA beats RDP for both CPU and Bandwidth consumption.

http://www.brianmadden.com/blogs/gabeknuth/archive/2009/06/18/redhat-spice-vs-rdp-vs-ica-performance-video.aspx

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