Archived from groups: alt.internet.wireless (More info?)

My experience with wireless networking has been less than encouraging.
At home or at the office, the connection is not 100% reliable. I do
freelance tech work and I am now being asked to install a wireless
network for a medical office. The best product I've ever uses came
from Orinico (proxim now?), Cisco Aironet has also been good. Can
anyone make recommendations for a reliable industrial strength
wireless network that will not suffer from lost connections? Is there
any such thing?

Thanks

Archived from groups: alt.internet.wireless (More info?)

On 13 Oct 2004 07:05:38 -0700, nedhart@hotmail.com (Ned Hart) wrote:

>My experience with wireless networking has been less than encouraging.
> At home or at the office, the connection is not 100% reliable. I do
>freelance tech work and I am now being asked to install a wireless
>network for a medical office. The best product I've ever uses came
>from Orinico (proxim now?), Cisco Aironet has also been good. Can
>anyone make recommendations for a reliable industrial strength
>wireless network that will not suffer from lost connections? Is there
>any such thing?

We'll have 100% reliable wireless when we have 100% reliable medicine.

Cisco and Proxim (Orinoco/Avaya/Agere/Lucent/Wavelan/Whatever) are
good products. If all you had to do is buy the "right" product, you
would have close to 100% reliability. However, you're not alone in
the wireless world and the 2.4GHz band is not your exclusive domain.
There are other users, microwave ovens, frequency hoppers, Bluetooth,
cordless phones, X10 TV links, plastic pre-heaters, RF excited lights,
ham radio, and other sources of interference. If this medical office
is in a high office building and exposed to such RF interference
because of its view of the surrounding metropolis, you're not going to
get anywhere near 100% reliability. Given sufficiently adverse
circumstances, you may not even be able to maintain a connection.

There's not much one can do to insure reliability other than massive
redundancy. That means 1 access point per room and a central router
to deal with soft roaming handoffs. My favorite of the week is:
http://www.symbol.com/products/wir [...] witch.html
However, this will do nothing if the client radio is the one picking
up the interference. A smart access point (wireless switch) isn't
going to work at all if the client radio is deaf.

Another form of redundancy is to use both 802.11g (2.4Ghz) and 802.11a
(5.6Ghz). There are cards that will do both and select the "best"
connection. If one band is trashed, the other takes over. I've never
actually done this but have heard of others doing this to improve
reliability. Most commodity grade manufactories have dual band
(802.11a/b/g) radios and access points. Cisco and Proxim apparently
do not.

Another method is to control the antenna pattern. This is tricky
indoors but the idea is to prevent any inside antennas from hearing
outside interference. Again, the problem of interference to the
client radio makes this method less than useful.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558

Archived from groups: alt.internet.wireless (More info?)

Ned Hart said the following on 10/13/2004 7:05 AM:
> My experience with wireless networking has been less than
> encouraging. At home or at the office, the connection is not 100%
> reliable. I do freelance tech work and I am now being asked to
> install a wireless network for a medical office. The best product
> I've ever uses came from Orinico (proxim now?), Cisco Aironet has
> also been good. Can anyone make recommendations for a reliable
> industrial strength wireless network that will not suffer from lost
> connections? Is there any such thing?
>
> Thanks

Here at the university we use Enterasys products for our wireless access
points (a/b/g). They're definitely not a consumer oriented company like
Linksys, Netgear and D-Link.

I just had an Roamabout RBTR2 access point installed to cover some
student areas ($1500!!) and find that in our office/classroom building
we can get good to excellent signal coverage within 45~50 ft of the
transmitter.

http://www.enterasys.com/products/wireless/

Lance
*****

Archived from groups: alt.internet.wireless (More info?)

On 13 Oct 2004 07:05:38 -0700, nedhart@hotmail.com (Ned Hart) wrote :

>My experience with wireless networking has been less than encouraging.
> At home or at the office, the connection is not 100% reliable. I do
>freelance tech work and I am now being asked to install a wireless
>network for a medical office. The best product I've ever uses came
>from Orinico (proxim now?), Cisco Aironet has also been good.

Most brand name products are pretty good and reliable - you should
base your selection on the availability and quality of local repair
and support facilities. I use Netgear, and have had no problems.

>Can anyone make recommendations for a reliable industrial strength
>wireless network that will not suffer from lost connections? Is there
>any such thing?
>
All 802.11b/g products can suffer connection reliability problems
because they share the 2.4GHz band with a host of other products that
can cause interference and loss of signal. A medical office and
surgery can also be a goldmine of interfering sources!

You may care to investigate 802.11a products - up in the 5GHz range
with less interfering products, but higher attenuation and less range
- which can be catered for during installation. 802.11a products are
rarer but tend to be used more in industrial offices, although 11g
seems to be taking over. My own laptop has a WiFi card that scans for
11a and 11b/g networks but it hasn't found an 11a anywhere in Sydney
yet - you may have difficulty getting 11a routers with good local
support.

I would suggest a combined wireless - wired solution. The static
terminals can be hard wired with 100MHz ethernet connections to the
router while only the laptops need to use the 802.11g wireless.
That's what I use, and that's what my daughters surgery is about to
use too.

I also have a couple of spare wired ethernet points to the router into
which I can plug laptops when I want to do system backups - the 100MHz
ethernet does the backups much quicker than the 11MHz/54MHz speeds of
802.11b/g. My laptop automatically switches from the wireless to the
ethernet when I plug in the ethernet cable. It's all magic as far as
I'm concerned.



--
Regards,
Peter Wilkins

Archived from groups: alt.internet.wireless (More info?)

On Wed, 13 Oct 2004 12:24:58 -0700, Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:

~ Another form of redundancy is to use both 802.11g (2.4Ghz) and 802.11a
~ (5.6Ghz). There are cards that will do both and select the "best"
~ connection. If one band is trashed, the other takes over. I've never
~ actually done this but have heard of others doing this to improve
~ reliability. Most commodity grade manufactories have dual band
~ (802.11a/b/g) radios and access points. Cisco and Proxim apparently
~ do not.

?

We do indeed sell dual band (802.11a/b/g) client adapters
(CB21AG for Cardbus and PI21AG for PCI) and APs (AP1200,
with more coming.) I will concede that we are not "commidity grade".

Cheers,

Aaron

Archived from groups: alt.internet.wireless (More info?)

On Thu, 14 Oct 2004 09:52:37 -0700, Aaron Leonard <Aaron@Cisco.COM>
wrote:

>On Wed, 13 Oct 2004 12:24:58 -0700, Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>
>~ Another form of redundancy is to use both 802.11g (2.4Ghz) and 802.11a
>~ (5.6Ghz). There are cards that will do both and select the "best"
>~ connection. If one band is trashed, the other takes over. I've never
>~ actually done this but have heard of others doing this to improve
>~ reliability. Most commodity grade manufactories have dual band
>~ (802.11a/b/g) radios and access points. Cisco and Proxim apparently
>~ do not.

>?
>We do indeed sell dual band (802.11a/b/g) client adapters
>(CB21AG for Cardbus and PI21AG for PCI) and APs (AP1200,
>with more coming.) I will concede that we are not "commidity grade".

Oops. Thanks. I wasn't aware that Cisco sold dual-band AP's. (My
experience with Cisco ends with the 350 series). I did search the
Cisco web pile for product info and didn't notice them. With the help
of the product model numbers, I was finally able to find URL's.

http://www.cisco.com/en/US/product [...] index.html

http://www.cisco.com/en/US/product [...] ebc29.html

http://www.cisco.com/en/US/product [...] ebc33.html

To be fair, I also screwed up on Proxim products. The AP-2000 can
handle a mix of two cards, while the AP-4000 comes stock with both
bands.
http://www.proxim.com/products/wifi/ap/

Drivel: Time for try #4 of tearing the power steering pump out of my
truck and plugging a cracked housing leak. Nice way to waste the
day...


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann wrote:
> On Thu, 14 Oct 2004 09:52:37 -0700, Aaron Leonard <Aaron@Cisco.COM>
> wrote:
[snip]

> To be fair, I also screwed up on Proxim products. The AP-2000 can
> handle a mix of two cards, while the AP-4000 comes stock with both
> bands.

For just a little more info, the AP-4000 has three bands and can handle
11b/11g on one antenna, 11a on another. From what I have seen the 11a
side of things is usually a backhaul with a directional. It has four
antenna interfaces to use. I currently use the two 11b/11g side of
things with an omni on the roof, and a low gain proximity for the inside
local stuff. My roof antenna is a 21db, and we were getting 22M
connection right below it, through two building interfaces ( roof, 2nd
story ) which translated into about 3M bits/per going to the Internet.

When I was doing the research on the proxim, I found that the older
firmware models were screwing up the beacon timing and would only
connect at 11b if a 11b card came on line. Seems that this
....feature... has been fixed as I have both flavors connected. I
haven't used the 11a side yet as I am negociating with a taller building
further north to extend our reach...

> http://www.proxim.com/products/wifi/ap/
>
> Drivel: Time for try #4 of tearing the power steering pump out of my
> truck and plugging a cracked housing leak. Nice way to waste the
> day...
>
>

Drivel, wonderful thing isn't it. I have a Bronco 5speed that doesn't
go into first that I get to play with!

Y'all have a great weekend!

tod

Archived from groups: alt.internet.wireless (More info?)

Than you for sharing your experience with me. I have some reading to
do, but I feel a lot more prepared now.

Thanks
NH