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From: diamant@hpfclp.SDE.HP.COM (John Diamant)
Newsgroups: comp.windows.news
Subject: Re: is news loosing the battle?
Message-ID: <10250002@hpfclp.SDE.HP.COM>
Date: 4 Jul 88 17:25:12 GMT
References: 
Organization: HP SDE, Fort Collins, CO
Lines: 102

> 	2) The next questions are : what is the staying power of
> 	   X given NeWS' availability on similar platforms?  Will the
> 	   future simply be NeWS/X window managers or just one or the
> 	   other?  I don't think too many people are arguing that X11
> 	   is technically better ... rather more people tend to argue
> 	   the reverse (surprisingly even some of the X folks concede
> 	   the point) ...

Whoa, there.  Interesting that you chose to post this in a NeWS only group.
In an X group, I'm sure you'd get quite a bit of disagreement on this.
Before I begin, let me say that I'm in the X camp myself (I'm an experienced
X programmer, have seen NeWS and believe I understand the basic model, but
am not a NeWS programmer, so feel free to correct any technical errors
regarding NeWS -- which I'm sure you would even without an invitation :-)

Both NeWS and X have technical advantages, but I don't believe one is
fundamentally superior to the other.  However, X has from the beginning, been
a completely open system, whereas NeWS has been an expensive, licensed piece
of software until the introduction of the AT&T NeWS distribution.  Now that
NeWS will be more freely available, NeWS and X can compete on equal footing.
Until now, it was a simple choice:  do you want a proprietary system which one
vendor is trying to foist on the world (NeWS) or a multi-vendor, open system,
which has been freely available from the very start (X).

NeWS advantages over X:
high power imaging model (2D) using absolute dimensions, rather than pixels
non-rectangular windows
Postscript available
Toolkits can be interpreted in the server, and thus substituted out from under
	the application
mimimal traffic between client and server

disadvantages of NeWS relative to X:
requires relatively powerful NeWS server -- a NeWS terminal will be more
	expensive than an X terminal
programming process context switching and partitioning between client and
	server is a PAIN for the progammer.
programming in Postscript is a pain (of course, Sun provides a C translator
	so this isn't that big a problem).

Now, let's examine the NeWS advantages for a moment and see how important they
are.  Regarding the imaging model, it is only 2D, and X is getting the
3D graphics extensions defined as a standard extensions, so any vendor with
good hardware for graphics will probably support it.  The issue of absolute
dimensions and font scaling is a real one, though, of course, there are
workarounds in a pixel based system (adjusting depending on the screen size).

Non-rectangular windows is "gee whiz," but frankly, I don't care about that
at all.  Other than having round clocks, I just don't see this as a big deal.

Postscript will be available on X as well, thanks to Display Postscript and
some public Postscript previewers.
(please note my distinction of the imaging model and just having Postscript --
this item addresses the display of Postscript and the output language only)

The ability to have interpretive toolkits which can be swapped is useful, but
there are other ways to accomplish this in X as well (using dynamic loading,
for instance).

Probably the most significant difference between X and NeWS is the traffic
between client and server.  First of all, Scheifler wrote a paper about why
the traffic breakdown wouldn't be as good as the claims (because the
communication for even simple operations like menus would be higher than
expected).  Second of all, it doesn't really matter!  I'm a network
administrator and I have some experience on this subject.  Lan bandwidth is
rarely the bottleneck in communications between two machines.  We run
diskless (including remote swap), remote X, etc. and the volume of traffic
is just never that high (typically under 5% of lan utilization).  Also, most
X servers run with Unix Domain sockets when running locally, so lan overhead
isn't a big issue.  The only issue that remains is the performance in terms
of throughput on the lan.  We are already at the point where lan performance
is within the same ballpark as disk transfer rates, so it isn't that big a
deal, and we're getting faster lan technology too.

The only time this will really matter is for non-local lans, like SLIP remote
links or over low-speed remote channels.  In that case, I concede that NeWS
has an advantage, but that is probably only a small percent of the use of
either NeWS or X, and running at 9600 baud over SLIP for X will still be
acceptable, I believe.

Basically, the assumptions that X used were that a high-speed byte stream
was available between client and server and that the client was a more powerful
machine than the display server.  NeWS uses a different set of assumptions
(or at least it shines in a different environment).  NeWS is best when the link
speed is low and the client and server are roughly the same power.  That means
if you have a Sun workstations at home, then you are probably best off running
NeWS remotely, but if you have a PC or a custom window terminal at your desk,
you're better off running X.

> 	One more note : I tend to think that those companies that
> 	offer both systems are in a much better position than those
> 	companies only offering X...

This is probably true, at least until things settle out.

Disclaimer: These opinions are my own and do not necessarily reflect those
	    of Hewlett-Packard.

John Diamant
Software Development Environments
Hewlett-Packard Co.		ARPA Internet: diamant@hpfclp.sde.hp.com
Fort Collins, CO		UUCP:  {hplabs,hpfcla}!hpfclp!diamant