VNC versus Sunray
Mon Apr 28 13:10:01 2003
> -----Original Message-----
> From: Dave Warren [mailto:firstname.lastname@example.org]
> > > Is VNC protocol compatible with SunRay?
> > I don't know the SunRay protocol. I think vnc, SunRay, Cytrix MetaFrame,
> > X-terminals, M$TerminalServices all use a similar protocol that provide
> > keyboard video and mouse services to the desktop. Some provide more than
> > that, others are restricted. Some need a high bandwidth, some low.
> There are two different ways of moving programs/desktops to remote
> VNC is one method, it moves a bitmap (compressed in some form, or not,
> depending on your configuration) from the server to the client, all the
> client does is display the data.
> X-terms and Terminal Servers operate differently, they actually transmit
> instructions from the server to the client describing how to create the
> window (Draw window X by Y, put text "x" at coordinates "x,y" using font
> "z", etc) -- This is a lower bandwidth solution, but it often requires
> CPU power and/or a smarter client. There will also be the ability to
> transmit bitmapped graphics as well.
I don't know if you do know the bandwidth requirementes for an X11 session
but I do know that a minimal X11 configuration with respect to the bandwidth
requiremnets is absolutely not workable on a double ISDN cononection (e.g. 2
* 64 Kbit, 128 Kbit). A VNC session is acceptable on a modem connection
(30Kbit)... BTW: This is my experience somewhere in 1998 with X11R4 and VNC
R3.3 all in default setting. I don't know current X11 implementations but
X11R4 has no compression by default where vnc does it by default. You are
right to say that X11 apps work on a draw-this draw-that base, my experience
tell me that for X11 it results in a higher bandwidth requirement.
For M$TerminalServers (and Citrix/ICA stuff) I don't know details.
> As to which SunRay uses, I don't really know.
> > To answer your question, I don't think it is compaTIble, I do think it
> > compaRAble.
> Agreed, to some extent.