Wireless bridge setup questions

I have a research farm that is getting a new supervisor and hw would
like to have the internet ported over to the house from the calving
barn. Not a big deal but I would really appreciate some feedback from
some people that have more experience than myself in setting up the
bridge.

I am planning on having the wireless router in the calving area, since
that is where the majority of the people are as well as the print
server. I was thinking of mounting an outdoor omni directional antenna
paired with a 1W amplifier to get some range around the farm and then
on the house mount a directional antenna aimed towards where the
calving barn is also with a 1W amplifier and a repeater inside the
house connected to the antenna.

Does this sound somewhat along the right approach? I also do not know
if I need the amplifier for the house or not, but seeing in terms of
time vs cost of an amplifier I figured it's best to order one and use
it rather than waste time that will cost more than the amplifier.

I am also looking for specific equipment recommendations for what I am
setting up.


Thanks in advance.

> paired with a 1W amplifier to get some range around the farm
> and then on the house mount a directional antenna aimed
> towards where the calving barn is also with a 1W amplifier
> and a repeater inside the house connected to the antenna.

Boosting signal beyond a certain point is illegal, and the fines can be stiff. Just as importantly, boosting signal at the access point will not help you if you are trying to connect to it with a laptop or some other low powered device since they will not be similarly "boosted." There also will be heavy self-interference if you do boost signals on connecting radios, since the sensitivity of the radio will be much higher than the gear designed for higher powered usage. You don't mention whether it's a 802.11 bridge you plan to use, but I'll assume it is.

If you don't require mobilility, something like a Tranzeo 802.11a bridge should provide what you are after and works cleanly to over a kilometer (more is very possible with different antenna choices). I have some used Tranzeo gear for sale (cheap) if there is an interest.

If you require mobility then likely that will mean either several access points placed around the are and wired together or equipping the end users with high powered gear.

Lots of choices available, 3Com has some good campus gear, etc.

Don't try to shoehorn low-cost consumer wireless bridges into this job, you are guaranteed trouble.
--
Steve Cole
President, Kingston Online Services
http://www.kos.net/.
Posted from WISP Forums: www.wispforums.com

Steve wrote:

> Boosting signal beyond a certain point is illegal, and the fines can be stiff. Just as importantly, boosting signal at the access point will not help you if you are trying to connect to it with a laptop or some other low powered device since they will not be similarly "boosted." There also will be heavy self-interference if you do boost signals on connecting radios, since the sensitivity of the radio will be much higher than the gear designed for higher powered usage. You don't mention whether it's a 802.11 bridge you plan to use, but I'll assume it is.
>
> If you don't require mobilility, something like a Tranzeo 802.11a bridge should provide what you are after and works cleanly to over a kilometer (more is very possible with different antenna choices). I have some used Tranzeo gear for sale (cheap) if there is an interest.
>
> If you require mobility then likely that will mean either several access points placed around the are and wired together or equipping the end users with high powered gear.
>
> Lots of choices available, 3Com has some good campus gear, etc.
>
> Don't try to shoehorn low-cost consumer wireless bridges into this job, you are guaranteed trouble.
> --
> Steve Cole
> President, Kingston Online Services
> http://www.kos.net/.
> Posted from WISP Forums: www.wispforums.com

The amplifiers I am looking at are from HyperLink technologies and say
they are fully FCC compliant for 802.11, which you were correct in
assuming. I am assuming that these would be within regulation to use,
but I may be incorrect in assuming this.
Part of the problem right now comes from the fact that I do not know
the exact layout, yet, of the farm area. In terms of mobility, I do not
know what they are wanting exactly, yet again lack of information that
is being given to me, so I am assuming that they will want a bit of
mobility around each area.

The main objective I want to get done is to be able to connect to the
wireless at the house, or at the barn and also have the spots linked
together. Add to the fact that my wireless experience past basic
installs consisting of a few AP's a repeaters does not help me much
here.

I am hoping to get out there tommorow and get some distances and
location of things via a GPS. Once I have distance and obstacles in
mind I should be able to get a better idea in what I want and don't
want.

On 17 Jan 2007 12:56:33 -0800, "Raptor" <I_AM_Raptor@hotmail.com>
wrote:

>Does this sound somewhat along the right approach?

No. Not even close.

The problem is that you've supplied absolutely no numbers from which
an appropriate recommendation can be assembled. There's also no clue
as to whether there is an internet connection involved, it's
bandwidth, and where it is currently located. What you need is
dependent on some calculations involving range, topology, line of
sight, Fresnel zone, required bandwidth, number of connections, type
of traffic expected, and number of client computers. The range and
line of sight are especially important.

I'm not sure I could supply a complete list of requirements sufficient
to offer a recommendation, but for starters, I would ask:
1. Range. How far between house and barn?
2. Line of Sight? Include elevation of antennas at each end so that
Fresnel Zone can be calculated.
3. Traffic and bandwidth? How much bandwidth do you need between
sites? Are you going to be doing high speed video over the link, or
just casual web browsing? VoIP? Backups?
4. Dollars? Is there a budgetary limit?
5. How many connecting computers? Laptops? Wireless or Wired?
Expected coverage area or radius? Connected to both ends?
6. Any existing equipment that needs to be accommodated?

There's probably more things that would be useful, but this is a good
start. It's highly likely that you will NOT need an amplifier as this
creates an "alligator". That's an animal with a big mouth and small
ears, that talks far farther than it hears. Such amplifiers are only
useful for extending the range if both ends of the link have similar
power amplifiers. Otherwise, they are just interference generators.

I can't tell why you mentioned using a high gain omnidirectional
antenna for what appears to be a point to point link. Do you expect
wireless clients to connect to this omni antenna and then to the
internet? That might make sense if the wireless device at this omni
antenna was also a wireless router with an internet connection.
However, if the internet is at the other end of a WDS bridge, such a
link will result in at least a 50% maximum bandwidth reduction.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558 jeffl@comix.santa-cruz.ca.us
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

I have a setup going over a mile using just off the shelf D-link 800 AP
and D-link 810 bridge. Of course they are tied to a couple of
directional antenna (dbperformance.com). This setup has been flawless
for the past 3 years. I would not spend the major bucks for commercial
access points and bridge if you can find the Dlink stuff.

"Black Adder" <pdj@uniserve.com> hath wroth:

>I have a setup going over a mile using just off the shelf D-link 800 AP
>and D-link 810 bridge. Of course they are tied to a couple of
>directional antenna (dbperformance.com). This setup has been flawless
>for the past 3 years. I would not spend the major bucks for commercial
>access points and bridge if you can find the Dlink stuff.

Nice.

Big antennas make a BIG difference. There's also a direct
relationship between speed and range (for a given antenna
combination). +6dB gain increase means double the range (at the same
speed). +12dB increase is 4 times the range. +18dB is 8 times. Etc.

Going from the stock +2dBi rubber ducky antennas, to big +24dBi
barbeque grill dish antennas at each end, is a 44dB gain increase.
10^(dB/20) = 10^(44/20) = 160 times
the range of the rubber ducky antennas, again at the same speeds.

The range also varies with the connection speed mostly because the
receiver sensitivity decreases with increased speed. Very roughly, if
you double the connection speed, the range decreases by a factor of
0.70. This works well for OFDM 802.11g speeds, but not for comparing
802.11b with 802.11g speeds.

<http://www.dbperformance.com>
Interesting antennas. The datasheets on the web page looks like they
actually ran pattern tests on their antennas. However, I'm a bit
suspicious about the advertised gains. Seems a bit high for the size
of the antenna.

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Well, got a chance to go and get a view of the area they want wireless
installed.
And I must say it was a bit misrepresented in terms of how far it is
between the areas they want access from.
When I got there I could already easily see the one spot visibly from
where the house is. But just to make sure I used a GPS to check the
distance, and sure enough, it's not all that far.
The distance between the two is 850ft with almost nothing inbetween.
I had a DLink 1310 with me and figured I'd see how far it would get
outside of the building I placed it in, which the metal clad barn. I
just about made it to the house with its original omni antenna scanning
with my Toshiba laptop.
Glad I didn't commit to much into this before getting out and viewing
the spot.
I'm thinking now that am outdoor omni antenna at the barn with a omni
repeater at the house will cover everywhere they want to be with their
system. No need for any amplifiers or long distance bridging.


Anyway, now I just need to find an outdoor antenna that is rated to at
least -40 degree operating tempature.

On Wed, 17 Jan 2007 16:58:16 -0500, in alt.internet.wireless , Steve
<shaman[at]kos[dot]net> wrote:

>Boosting signal beyond a certain point is illegal, and the fines can be stiff. Just as importantly, boosting signal at the access point will not help you if you are trying to connect to it with a laptop or some other low powered device since they will not be similarly "boosted." There also will be heavy self-interference if you do boost signals on connecting radios, since the sensitivity of the radio will be much higher than the gear designed for higher powered usage. You don't mention whether it's a 802.11 bridge you plan to use, but I'll assume it is.

Steve if you intend to continue posting here, please configure your
newsreader properly so that it wraps lines at ~70 chars. I presume
that FUDForum can do this, if not I suggest getting one that can. At
present your posts are largely illegible.

--
Mark McIntyre