I wrote some time ago about remote access to poplog/Pop-11, e.g.
from a Windows machine using a web browser:
> Textual interaction would not be too hard (as in eliza), but
> allowing graphical commands (using rc_graphic or rclib for example)
> would probably be very difficult (except for users who alread have a
> local X server running).
>
> I believe those that are available for Windows are not cheap (e.g.
> eXceed costs over $500).
Since then things have developed.
Our department is willing to allow school teachers who wish to
experiment with remote access to a linux machine from a windows or
from a lightweight local linux machine, to access one of our linux
servers, for an experimental period.
I hope to be talking about some of the things that can be done with
Poplog/pop-11 at the Open Source Schools project "Unconference" on
Monday 20th July, in Nottingham
http://opensourceschools.org.uk/unconference09
If anyone knows of a school in the uk that might be interested in
trying this remotely please ask them to email me. It's not only
poplog that would be available.
NB:
I have learnt that there is a tool called Xming that is freely
available for use on Windows, in conjunction wiht an ssh client,
like PuTTy, to access a remote linux machine.
Provided that the ssh connection is set to permit X11 tunnelling,
Xming acts as an X11 server and when I tried this on my wife's
machine, logged in either to my linux PC at home or (via 20MB/sec
cable modem connection) to a university linux machine, it worked
extremely well. XVed worked as expected, and all the RCLIB demos
shown in this file worked
http://www.cs.bham.ac.uk/research/projects/poplog/figs/rclib/
as well as SimAgent demos
http://www.cs.bham.ac.uk/research/projects/poplog/figs/simagent
There was a slight delay when opening a new window, but once it was
on the screen, interactions with it, and drawing on it were pretty
fast. Of course, this depends on the connection speed and could be
painful with a slower link.
XMing can be downloaded from here:
http://www.straightrunning.com/XmingNotes/
A detailed tutorial on how to install and set up Xming is here:
http://gears.aset.psu.edu/hpc/guides/xming/
They recommend installing PuTTY separately from xming.
One advantage of having PuTTY separately (or the SSH Secure Shell
Client) is that for each remote host to be accessed you can run
PuTTY, set up a profile, and save it.
Moreover, it is important to ensure that you use PuTTY's
configuration options (on left), expand SSH, go to X11, select
Enable X11 forwarding
MIT Magic-cookie
as shown in the section of the above tutorial headed
Configure X11 Forwarding in SSH Clients
(then go back and save the configuration for future use).
If instead you use the SSH client, select "Tunnel X11 Connections"
as shown in the tutorial.
The basic idea is that if you have Xming running (it shows on the
task bar) you can log in securely to a remote Linux/Unix machine
using PuTTY or SSH, then once logged in you can run an xterm window
and run graphical programs on the remote machine that will use the
local display (via Xming).
(That's the great benefit of the X Window System).
=========================
I have heard that there may be another possibility that does not
require a special tool like Xming to be installed locally, but uses
only a Java-enabled web browser. Namely if there is a VNC server on
the remote machine, a user can access it remotely via a web browser,
which will then fetch and run a java script that emulates an x11
server.
Has anyone tried using VNC like that? Can different users access the
same vnc server and have their interactions kept separate? (I know
that for teaching purposs VNC can support different users seeing
exactly the same display, but that's not what would be desirable for
remote access to poplog for learning progamming.)
My impression is that doing things that way does not give the
security benefit of using ssh plus X11 tunnelling, but I don't
understand enough about VNC to be sure.
The great advantage of something like Xming is that it allows a
windows PC to be used simultaneously for accessing a remote linux
server and running windows programs as usual (e.g. email). there is
no need to reboot and no need to install a VM system with linux
running in it.
Aaron
http://www.cs.bham.ac.uk/~axs
