The NX protocol is basicaly a successor to the X protocol and very nyce for Streaming. NoMachine implements that and is a better VNC with video streaming and a nice alternative to TeamViewer with good cross-platform capabilities. Also keyboard and mouse works cross-plattform without any problems. This is an issue with most alternatives to TeamViewer. Yet TeamViewer still is number #1 for me.
In 2001, the compression and transport protocol NX was created to improve on the performance of the native X display protocol to the point that it could be usable over a slow link such as a dial-up modem. It wrapped remote connections in SSH sessions for encryption.
The NX scheme was derived from that of DXPC – the Differential X Protocol Compressor project. NX 1.x was released to the general public on February 14, 2003, the final version of ‘NX’ being 3.5. The last update of 3.5 was in 2012.
The core compression technology up until NX 3.5 was made available to the community under the GNU GPL2 license whilst other components such as the NX Server and NX Client programs were proprietary.
In 2009, Google made a freely available Open Source GPL2 version of the server called Neatx. Other open source variants of NoMachine’s NX are also available (see below).
Starting in 2013, with the release of version 4.0, NX technology became closed source.