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View Full Version : NX Server? How's that possible?



thomas_remkus
03-24-2005, 02:09 PM
I am very new to running NX Server and have tested this with Knoppix 3.7 with a Windows client. It runs awesome! I had absolutely no issues with my first round of testing. My question is this: when looking at the NoMachine website I see this application is for purchase. How can Knoppix have this for free? Is it really free? Will it be disabled over X time? It seems to strange to me to have something so awesome for free ... from a Windows standpoint we're talking heracy. Last question, how can I get the NX Server on Knoppix to always have NX Server start on boot and also start my ssh server too?

UnderScore
03-24-2005, 04:51 PM
I don't have much experience with NX so I can not help with the technical side. But as far as the freedom or inclusion of NX in Knoppix, much of NX is licensed under the GNU GPL. See http://www.osnews.com/story.php?news_id=8139&page=1 for more about Knoppix, NX and GPL.
I hope this helps.
James

garyng
03-28-2005, 09:58 PM
The core technology of nomachine is licensed under GPL. Freenx(the server side) is implemented seperately as a collection of scripts and the pseudo X server(like VNC).

Once installed, nxserver is enabled by default and can be used on boot(so long you have sshd running). What essentially is freenx is that it is a wrapper of ssh and VNC(well, not exactly VNC but technically similiar stuff). It goes like this :

The client establish a SSH session to the server using specific username(nx)

The login is through RSA key so no password is needed for this part

Once login, the server side instead of running a shell, it runs another program that handle the true user login(using PAM, just like any unix login).

Once this login is successful, it lauches an X server(more or less like VNC) and the client side then talks with it.

The difference between nomachine and VNC is that nx performs some X protocol level compression which makes it very suitable for slow link(VNC is purely image change detecting/compression).

You can achive the same thing using VNC+SSH, just more cumbersome. Some VNC variants do provide some automation as well but not the X protocol optimization though.

nx has another advantage, remote sound which will soon be in freenx(the commerical server has it already). This is not easily duplicatable in VNC.