JC -
One more comment on Petreley - he is a big fan of X. Although his comments on the difficulties Citrix has encountered in supporting multiple user contexts on NT are all true - in fact they couldn't do it on standard NT - he glosses over the weaknesses in X with some questionable statements.
he says X allows the meat of the application to run at the server and simply display and take input from the remote terminal or workstation.
True as far as it goes. But of course X was developed when a full-up RISC workstation was well over $10K, and $10K was a whole lot more money than it is today, so the protocols were designed to minimize the intelligence required on the client. As a result, the cut point on the interface is high - the client knows much less about the properties of screen objects than a Citrix MetaFrame client knows. I can run a MetaFrame client with a display resolution of 1280 by 1024 over a 28K modem and get good response - plenty usable for remote access and even remote development and debug. Try that with X... even on DSL, X is a sloth. Nice and snappy on 100M EtherNet though...
He goes on to say X11 is harder on a network wire because it is more distributed.
This is EXACTLY BACKWARDS!! X is LESS distributed. The bandwidth us used because the client can not deal in metadata and must request every component of the display from the server.
He goes on to compare the number of users between an NT server supporting Citrix and a Unix system supporting X - and correctly points out that the Unix box, even running the X engine, has only a fraction of the load of the NT system, and can support a lot more users. That is, as he says, because the Citrix system has to not only manage the graphics interface but also has to "fake out" NT and manage all of the individual user contexts.
While I agree with his criticisms of NT in that regard, there is no comparison between X and the MetaFrame architecture. I have been playing with the beta MetaFrame engine for Solaris, and it has better performance and less server load than X at a fraction of the network load. I also have the ability to run any mix of apps (NT or Solaris) on any client, NT or Unix - as soon as I get all my 11 MB wireless shaken out fully, that will be a big benefit, especially sitting by the pool...
Take a look at citrix.com
if you're interested. |
