Setup of Wireless LAN for thin client network

[Stephen Liu]

Hi Jim,

Thanks for your detail advice.

>On Fri, 14 Nov 2003, Stephen Liu wrote:
>  
>
>>I am running a thin client system - LTSP/K12osn.  Each diskless desktop
>>workstation is without hard drive.  They are connected to the server via
>>a switch and running X server (X window) from the latter on their screen
>>and booted with a rom on NIC.  Notebook connection is also possible
>>booted from floppy with a booting image installed.
>>
>>Now I am prepared to convert the system to Wireless LAN.  According to
>>suggestion for diskless desktop workstation it is possible.  For
>>notebook chance is remote.
>>    
>>
>
>A number of years ago UCLA-Mathnet used a similar arrangement to good
>effect (on wired Ethernet).  However, as the cost of discs and
>general-purpose PCs went down we decided it was more cost-effective to put
>US$600 PC's on people's desktops, and to keep them updated by
>locally-written scripts.
>  
>
Thin client system is ideal for reviving those obsolete PCs, in addition 
reducing the administration cost.  You need to update the sever only not 
all workstations. 

One question popup to my mind for fat-client system could update the 
server simultaneously/collectively updating all desktops?  That is if I 
install a new package on the sever could it be installed on all desktops 
simultaneously/collectively?  Thin client system can avoid this 
problem.  As time elapses it is not so easy to find obsolete PCs.  Then 
the cost of a new thin client desktop won't have much difference to a 
fat client desktop.  If such point mentioned hereof could be solved the 
cost of administration can be reduced dramatically.

- snip -

>I encourage users to do on the local machine:
>    xterm -e "slogin -X serverhost"
>(using an alias or a menu item for the principal servers).  This puts most
>of the resource usage, for the xterm, on the local machine.  But when they
>use graphical apps on the server such as maple, matlab or mathematica,
>X-windows service is available.  But we tell them to run matlab on the
>local host too; our license scheme allows that.
>  
>
Could you please explain in more detail on ;

xterm -e "slogin -X serverhost"

Thanks

>On the wireless issue, the kinds of setup info (ESSID, WEP key) that's
>needed could easily be included on a boot floppy, but I doubt that a boot
>PROM would have the flexibility to handle this.  But who knows, you may
>have found a vendor with a smart boot PROM.
>  
>
If I have the booting image I can burn the ROM myself.  Another problem 
is I have not discovered a wireless lan card with rom socket on the market.

>If only a few people will use the system at a time, it should work OK.
>Certainly at home and at work I use my laptop with X-windows across the
>wireless net (though when possible I use the local xterm method) , but if
>you have 50 to 100 workstations I'm afraid that they would fight for
>bandwidth.  In comparison, your wired network switch can handle multiple
>connections simultaneously, so the total throughput is several times the
>nominal network bandwidth (10 MHz or 100 MHz), provided the users are
>distributed over several servers.
>  
>
Yes bandwidth is another question.  I will not put all desktops go 
wireless except in one or two location where it is difficult to lay 
cable.  My major interest confines on laptop booting.

>One possibility is a hybrid system: run wires to most of the clients, but
>for two or three that are impossible to reach, use wireless.  On the
>notebook computers, I would recommend using a general-purpose operating
>system so the users have freedom to do general-purpose work on them.
>I have a user support page for setting up a wireless card:
>    http://www.math.ucla.edu/computing/user_support/hardware/wiresetup.html
>
Thanks for your link.  I went through "SuSE Linux 8.1" section briefly.  
However I could not resolve if it is a thin client where can I have the 
new config stored.

ltsp.org has a booting image for floppy (I haven't tested it yet.  Only 
read it on a posting).  It boots the thin client and in turn boots the 
wireless PCI card which has a PCMCIA to connect the sever.  Whether the 
design of "Setting Up Your Wireless Network Card" is similar to ltsp.

Thanks

B.R.
Stephen