[KLUG Members] Wireless

[Bruce Smith]

> >At work we need to hook up a couple X-terminals to our network
> >in a location it is not a good idea to run copper (trust me -
> >long story).  So I figured the options are fiber or wireless,
> >the later being cheaper.
> 
> >Because these are X-terminals (and a jetdirect printer), I
> >cannot buy a wireless network card, nor a wireless PCMCIA card.
> >I want to know if I can use two access points???
> >
> >Would it work to buy two Linksys 802.11b access points (each with
> >a builtin 4 port switch) and put one on the main network and one
> >by the terminals?  (they are close to each other and in range)
> >
> >I do NOT want to create a whole new subnet for this, but I
> >simply want to extend our current private class B network.
> 
> I've never worked with wireless, but from general networking
> principles, it should work.  I'm assuming these "access points" are
> essentially 5 port switches where one port is wireless and the other
> 4 are ethernet?

I'm not exactly sure.  It's a 4 port switch with an antenna.

The ones we're trying now from Linksys are for home use with
a cable modem or DSL because it also has a WAN port for the
internet and some firewalling capabilities in the software
(which we don't need).

The two "access points" came in Friday, and in my playing 
with them, I can't seem to make them talk to each other.
That has me wondering if they only work with the wireless
network cards.  I emailed Linksys tech support, hopefully
I'll hear back Monday.

I'm sure we'll end up NOT using these for this purpose 
anyway since they have DHCP turned on by default, and if
they get reset to default settings by mistake (press of a
button), that'll really screw up our network.

Linksys (and others) make dumb "access points" without the
WAN, firewall, DHCP and other crap.  

Now to figure out if two "access points" can talk to each other.

> >Any problems with this setup?  I haven't used wireless at all.
> >
> >BTW, I'm aware of the security problems of wireless, and will
> >deal with that, I only need to know what hardware I need.
> 
> If this is a permanent installation and there will be a lot of
> traffic going to that jetdirect printer, it might be worth the cost
> of going to fiber.  I think top theoretical speed of wireless is
> 10 Mbit / second, with realistic more like 6.

Nah, these are two low usage X-Terminals on a shop floor.
They are only used to input data to the MRP software and
print work orders.

> If you can't use copper, I'm guessing that's because of
> EMI problems. 

Not exactly.  The problem is this is a metal poll barn type 
building, and every time it storms, lightning fries ports in 
the hub/switch and some times the X-terminal itself.  
Probably because the twisted pair is running across the 
building in it's metal frame.

> If so, you might have even worse EMI trouble with wireless
> unless you use an infrared solution, which will be even slower.
>  Don't know about that, though.  It's been a long time since I
> took E & M physics.

In theory wireless should work okay since the distance is within 
specs, the X-terminals are only running 10BT now, and there isn't 
a lot of electrical interference.  We'll see!  :-)

--------------------------------------------
Bruce Smith                bruce@armintl.com
System Administrator / Network Administrator
Armstrong International, Inc.
Three Rivers, Michigan  49093  USA
http://www.armstrong-intl.com/
--------------------------------------------