How to control LAN users?

[Styma, Robert E (Robert)]

 > 
>     I have a LAN with two Windows XP and one Apple Mac computers on it
>     in addition to several F7 Linux boxes.  The Ethernet connection is
>     via wireless Ethernet bridges at each computer and a 
> Netgear WGR614
>     wireless router at the Wildblue satellite receiver/modem. 
> 
>     I would like to be able to disable the Windows and Mac computers
>     individually when not in use without going to each one 
> and shutting
>     it down.  I know, tell the users to shut them off when 
> they leave. 
>     That doesn't work, they leave the house and the computers 
> remain on
>     and connected and I am accumulating mysterious usage on 
> this system,
>     presently 82% of what I am allowed for the month.
> 
>     I can probably disable the individual Ethernet bridges via the WEP
>     settings but then I may not be able to access them to 
> turn them back
>     on?  I could switch them to unused radio channels but then again
>     would I be able to turn them back on from here via the 
> LAN?  I think
>     not, they wouldn't "hear" me!
> 
>     I have looked through the Netgear setup information and 
> haven't been
>     able to figure a way to control them there although it seems to me
>     there should be a way and I may be missing something.
> 
>     The system works perfectly but it's out of my control, I 
> can't tell
>     whose using bandwidth as it stands.
> 
>     I would appreciate any thoughts or suggestions.
> 
>     Bob Goodwin
> 
There are a number of issues here which could be pursued.
First, in an ideal world, you say the users would power down
their computers when they leave.

You would like to be able to shut down or disable the machines
without having to go to the machine.  This implies that you have
a way of knowing that the user has left without actually checking.
You would become unpopular if you remotely shut down their machine
while they were in the middle of doing something.

One possibility would be to install VNC on each Windows/Mac machine in
service mode.
When you believe that they have gone, you could bring up their machine
and verify that the machine is not being used and also shut it down.
For the F7 machines, you could ssh over and bring up TOP to see if there
is any activity and then shut the machine down.  This would save power
as
well as achieving the desired end.
This is a manual process, but I did not see anything in your post which
precluded this.

Another line of thought is to determine what is using the network when
no-one is supposed
to be there.  You used the term "leave the house", so this could be a
residence.
If you have people coming into your house and using the computers, you
have more
serious problems than bandwidth usage :-)
In an office environment, the cleaning people could be using the
machines.  Setting the
machines to lock after a period of time would avoid this.

Some sites, like msn.com provide streaming content on their web sites.
This would continue
to use bandwidth while no one was there.  Another possibility is some
sort of malware.
Identifying the cause of the usage may be useful.

Some wireless routers allow you to cut off access based on time of day.
That may
or may not be worth looking at.

Just my 2 cents

Bob S
Phoenix, AZ