extending the range of 802.11g
Bootstrap Bill
802.11g (a free alternative to the Internet). The problem is 802.11g is
limited to about 300 feet.
What if everyone in my neighborhood had their own 802.11g router? Would it
be possible to somehow link them all together and create one giant network?
If so, would it be possible to roam within this network?
How big could such a network be? Could it cover an entire city? Multiple
cities?
Has this been tried before?
Will-Lee-Cue
Do a google search on this group and you will find a lot of information
about extending the range of of a wireless system.
Directional outdoor antennas at both ends could work for you and your friend
and might be the simplest way.
Access point at your house ... eithernet bridge at his.
Willam Lee
"Bootstrap Bill" <william...@gmail.com> wrote in message
news:juVne.16111$qJ3.11105@trnddc05...
Floyd L. Davidson
>I'm playing around with the idea of setting up a neighborhood wan using
>802.11g (a free alternative to the Internet). The problem is 802.11g is
>limited to about 300 feet.
More like 300 yards, but that doesn't really change your
problem. Do note that with high gain directional antennas
a line of sight distance of a few miles can be done too.
>What if everyone in my neighborhood had their own 802.11g router?
Well, you'd need 1 router and many clients, for each area
covered by a router. That area would vary greatly, as 802.11g
is a 2400MHz, and it simply does *not* go around corners or
through trees, or anything else. If you can see it, it'll go.
Hence an Access Point sitting on a 300 foot tower located on the
highest ground around... will cover a huge area. But an Access
Point in your basement might have trouble covering your second
story rooms. And every possibility between those will be
encountered.
The answer to that, is simply add more units configured as
Access Points...
>Would it
>be possible to somehow link them all together and create one giant network?
Sure. All it takes is money.
>If so, would it be possible to roam within this network?
Sure, with lots of money!
>How big could such a network be? Could it cover an entire city? Multiple
>cities?
>
>Has this been tried before?
That's what The Internet is. You're 2-3 decades late to get in
on the ground floor; but I gotta admit you have a *big*
imagination!
There are commercial companies providing ISP service using
wireless with coverage for entire cities. That takes some
serious investment in engineering and equipment.
A small network around a neighborhood could be done for a few
hundreds of bucks. Some of the more popular 802.11g radios can
be used as Access Points, Clients, Routers, Bridges, Point to
Point links, and probably something I'm not remembering.
Basically one model of that type (for example a Linksys WRT54G)
could be used to cover a large area by using many units. You
would need one location with access to the Interent. Then you
need however many locations for Access Point units as required
to provide coverage to everyone. Then you need pairs of units
to work as Point-to-Point links to connect each of the Access
Points to the location with the Internet connection.
At less than $80 each for the radios, you can engineer yourself
a network that only a few years ago would have cost hundreds of
thousands, or even millions, and do it for several hundreds of
bucks.
--
Floyd L. Davidson <http://web.newsguy.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) fl...@barrow.com
Bootstrap Bill
"Floyd L. Davidson" <fl...@barrow.com> wrote in message
news:873brzt...@barrow.com...
> Hence an Access Point sitting on a 300 foot tower located on the
> highest ground around... will cover a huge area.
How big of an area would a wireless G router mounted on a 300 foot tower
cover?
> The answer to that, is simply add more units configured as
> Access Points...
Off the shelf wireless G routers?
>
>>Would it
>>be possible to somehow link them all together and create one giant
>>network?
>
> Sure. All it takes is money.
>
>>If so, would it be possible to roam within this network?
>
> Sure, with lots of money!
A wireless G router costs less than $100. Each user would buy his/her own.
>>How big could such a network be? Could it cover an entire city? Multiple
>>cities?
>>
>>Has this been tried before?
>
> That's what The Internet is. You're 2-3 decades late to get in
> on the ground floor; but I gotta admit you have a *big*
> imagination!
>
My goal is to create a city wide free alternative to the internet. Free
meaning no connect fees. Each user would be required to buy his/her own
router.Eventually it might actually connect to the Internet, but for now I'd
be happy with a large intranet.
It would be a hobbyist project. Anyone could get in for the price of the
required hardware.
Is this doable? Could it be done at prices that hobbyists would be willing
to pay?
Bootstrap Bill
"Will-Lee-Cue" <n5...@stx.rr.com> wrote in message
news:SeYne.35955$6g3....@tornado.texas.rr.com...
> Your options are limited, Bill.
>
> Do a google search on this group and you will find a lot of information
> about extending the range of of a wireless system.
>
> Directional outdoor antennas at both ends could work for you and your
> friend and might be the simplest way.
> Access point at your house ... eithernet bridge at his.
>
> Willam Lee
>
>
What if I want my whole neighborhood to participate? Let's say that just
about everyone has their own 802.11g router (probably mounted on their
roof). Can they somehow form a large network? Would I need more hardware
than just the roiuters?
Once set up, would it be possible to roam around the neighborhood with a
laptop?
Will-Lee-Cue
(some of our best inventions were thought up by dreamers)
If you are planning to hook up the city to the internet for free what
connection are you going to use?
Are you going to lease a T1 connection to supply the internet service to
your network?
Dont think of using the cable company until you talk to them first.
They might have some ideas of their own about that.
Getting a signal out to cover a large area may be possable with a tall
antenna and a few watts of power but the person at the other end must use
enough power to get back to the your access point.
Inceasing the RF power would certinaly bring you under the control of the
F.C.C. and no doubt require a license of some sort.
From what you have posted I think you need to read up more on wireless
networks and how they work.
Placing a wireless router on every rooftop is not a workable option.
Even if you placed a wireless access point at every intersection in the city
and tied them all togather to a central location I doubt it would work like
you would want it to.
William Lee
"Bootstrap Bill" <william...@gmail.com> wrote in message
news:r91oe.78$KQ2.20@trnddc08...
yoplait
Visit this site ( all stoof for Boosting wireless and more )
http://www.hyperlinktech.com/web/wireless_booster.php
On Fri, 03 Jun 2005 21:28:28 GMT, "Will-Lee-Cue" <n5...@stx.rr.com>
wrote:
Jeff Liebermann
>Visit this site ( all stoof for Boosting wireless and more )
>http://www.hyperlinktech.com/web/wireless_booster.php
Dumb idea. Putting a power amplifier on an access point creates an
"alligator". That's an animal with a big mouth and small ears. It
can talk (and interfere) at a much larger range than it can hear.
Tropos Networks 1watt mesh network radios are a good example of an
alligator. The problem is that the amplifier doesn't really improve
the receiver sensitivity. If the access point is listening to a bunch
of low power laptop transmitters, the range will be no more with 1
watts belching from the access point, as with a power level equal to
the 35mw laptops, so the range will be symmetrical. In my never
humble opinion, power amplifiers are a great way to create
interference and nothing else.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# je...@comix.santa-cruz.ca.us
# je...@cruzio.com AE6KS
Jeff Liebermann
<william...@gmail.com> wrote:
>What if everyone in my neighborhood had their own 802.11g router? Would it
>be possible to somehow link them all together and create one giant network?
>If so, would it be possible to roam within this network?
Yep. There are SBC (single board computahs) available that are
designed for building "mesh networks". The basic idea is that each
"node" on the network is also a repeater. Eventually, the packets
arrive at the router that connects into the internet. This saves the
cost of having each node have its own connection back to the internet.
The problem is that it's a spectrum hog, suffers from bottleneck
issues, and relys heavily on a supremely complex routing algorithm.
Performance also sucks because each simplex node (that can only
transmit or receive one at time) cut the available bandwidth in half.
>How big could such a network be? Could it cover an entire city? Multiple
>cities?
The problem is that mesh networks do not scale very well at each
extreme. If there are a insufficiently small number of nodes, then
traffic may hit a dead end or go nowhere. If there are too many
nodes, then the bulk of the air time will be spent forwarding packets
in circles that eventually arrive, but rather slowly. There will also
be far too many collisions. Nodes with two or possibly three radios
that can do full duplex are a BIG improvement, but cost more.
Actually radios and infrastructer are only a small part of the
problem. Managing the system, maintenance, security, customer
support, enforcement, billing, interference mitigation, aluminium hat
RF exposure nuts, and the inevitable government "assistance", will all
be needed. Hardware also gets obsolete fast, so plan on replacing
literally everything every 5 years or so.
>Has this been tried before?
Yep, sorta. Metricom, Rooftop Networks (Nokia), and a bunch of
others. Horror stories and why they bombed if you want details.
http://www.muniwireless.com
http://www.tropos.com
http://pdos.csail.mit.edu/roofnet/design/
http://www.meshdynamics.com
http://www.firetide.com
http://www.meshnetworks.com (Motorola)
Plenty of others.
So much for the technical and on to the political. I'm the chair
personality, keeper of the faith, and bill collector for our
neighborhood association, road committee, defunct cable co-op, and
fiber/wireless network. In the past 30+ years I've lived in the
neighborhood, I've had to deal with all manner of neighborhood
cooperative efforts. Most fail. I would rather deal with the
government bureaucracy from hell than with some of the stupidity I've
encountered dealing with the neighbors and the fiber/wireless system.
I've literally paid for almost all the hardware myself and they treat
it like I run a public utility. If you value your sanity, I strongly
suggest you develop a paying business model and forget about being
nice. Otherwise, I hope you enjoy getting phone calls at 2AM asking
if the internet is up.
Richard Perkin
> I'm playing around with the idea of setting up a neighborhood wan
> using 802.11g (a free alternative to the Internet). The problem is
> 802.11g is limited to about 300 feet.
>
> What if everyone in my neighborhood had their own 802.11g router?
> Would it be possible to somehow link them all together and create
> one giant network? If so, would it be possible to roam within this
> network?
On a smaller scale to your vision, have a look at this:
<http://www.daszeltonline.de/wlan/>
If your German is not too good, look at the diagram and photos.
It's relatively easy to set up point-to-multipoint bridges like this.
They do not suffer from the same complexities as mesh networks, but
there is of course a bandwidth hit since the devices are single radio
and cannot receive and transmit concurrently.
Hope this helps
--
Richard Perkin
To email me, change the AT in the address below
richard.perkinATmyrealbox.com
It's is not, it isn't ain't, and it's it's, not its, if you mean it
is. If you don't, it's its. Then too, it's hers. It isn't her's.
It isn't our's either. It's ours, and likewise yours and theirs.
-- Oxford University Press, Edpress News
Jeff Liebermann
<william...@gmail.com> wrote:
>How big of an area would a wireless G router mounted on a 300 foot tower
>cover?
Avast ye maties. T'is a landlubber amongst us.
A good formula to remember is that the optical horizon is roughly:
range = sqrt (2 * height)
range = statute miles
height = ft
range = sqrt (2 * 300) = 24 miles.
http://pollux.nss.nima.mil/calc/horizon.html
Coverage area = Pi * r^2 = 3.14 * 24^2 = 1809 sq miles
Actually, the radio horizon is somewhat furthur than the optical
horizon, but NLOS (non line of sight) propogation at 2.4GHz is in my
opinion a crap shoot.
Your radio horizon will also be extended if you include the height of
the client radio antenna:
range = sqrt (2 * tower_ht) + sqrt (2 * client_ht)
range = statute miles
tower_ht = ft
client_ht = ft
For a 20ft high client antenna:
range = sqrt (2 * 300) + sqrt (2 * 20)
range = 24.5 + 6.3 = 30.8 miles
For extra entertainment value, drive around your area with Netstumbler
and estimate how many access points per square mile you find. Double
the number as about half are either not broadcasting their SSID or
cannot easily be heard from the road. Using my latest Netstumbler
maps, for Santa Cruz City, I'll guess a density of about 200 access
points per square mile. Therefore, if you deploy in an urban area,
you're looking at the interference caused by about 6,000 access
points. You can get similar results by simply taking a laptop and
decent antenna (panel or biquad) to the top of a tall office building
and running Netstumbler. My record is 190 access points in downtown
San Jose.
You do not want to know what it would cost to build and install a 300
ft communications tower. The Peoples Republic of Santa Cruz County
has an ordinance limiting towers to 52ft above average terrain and
about 15 ft for rooftops. Your local politics may vary.
--
Jeff Liebermann je...@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Bootstrap Bill
"Jeff Liebermann" <je...@comix.santa-cruz.ca.us> wrote in message
news:14g3a1lnrsmaff3je...@4ax.com...
> You do not want to know what it would cost to build and install a 300
> ft communications tower. The Peoples Republic of Santa Cruz County
> has an ordinance limiting towers to 52ft above average terrain and
> about 15 ft for rooftops. Your local politics may vary.
Who needs a tower?
http://www.cnn.com/TECH/space/9808/07/solar.plane/
Of course, it would cost far more than any group of hobbyists could afford
to pay.
Jeff Liebermann
<william...@gmail.com> wrote:
>"Jeff Liebermann" <je...@comix.santa-cruz.ca.us> wrote in message
>news:14g3a1lnrsmaff3je...@4ax.com...
>> You do not want to know what it would cost to build and install a 300
>> ft communications tower. The Peoples Republic of Santa Cruz County
>> has an ordinance limiting towers to 52ft above average terrain and
>> about 15 ft for rooftops. Your local politics may vary.
>Who needs a tower?
>http://www.cnn.com/TECH/space/9808/07/solar.plane/
It crashed in tests over Hawaii. That was also 1998. At the time, I
was maintaining a web page for alternatives to DSL and cable modems
for the San Francisco Bay area.
http://www.LearnByDestroying.com/nooze/wireless.htm
This is really old so don't expect all the links to work. I've kept
the page up beause it's become somewhat of a historical record of all
the great dot bomb type of ideas for providing last mile service.
Near the bottom is the science fiction section which includes the
airplane flying donuts in the sky, the teathered balloon repeater, and
a few of the many LEO and MEO satellite based financial disasters.
Ham radio field day is coming up in a few weeks. My grand plan is to
construct an inflateable tower. In theory, just pump it full of air
and up it goes.
http://www.boschaero.com/tower.htm
http://www.boschaero.com/movies/towers.wmv (5.3MB)
Photos and damage report next month.
>Of course, it would cost far more than any group of hobbyists could afford
>to pay.
It's difficult to justify even sharing the bandwidth when DSL at
1500/384kbits/sec now costs $15/month.
http://promo.yahoo.com/sbc/
Bob Smith
Your Idea about an inflatible tower is a good one,
a few field day's back (1988 or 1989 ) we had a 4sq inflatible
vertical setup for 160 and 8 meters with 8 weather ballons in
Humboldt countty.. Helium was to expensive ,, so we had a buddy that
had a tank of hydrogen,,,
worked good until sunday morning,, we head a 'pop' and on of the
ballons broke, caught fire and we a a 'hot' vertical for 160
No problems, the ballon was out before it landed, but what a trip,,
the verticals worked great..
Bob Smith
NA6T
Fort Bragg, California
Jeff Liebermann
>Your Idea about an inflatible tower is a good one,
I've been told by everyone involved that it either won't work, or is
useless if it does. That's a sure sign of a great idea and also my
secondary motivation to prove them wrong.
I saved enough vinyl from an old water bed to make a fair size tube.
However, I can't seem to make a decent seal. Everything leaks.
So, I went to commerical tubing:
| http://www.uline.com/Browse_Listing_2105.asp?desc=Black+Heavy+Duty+Poly+Tubing
| http://www.uline.com/Browse_Listing_2103.asp?desc=6+Mil+Heavy+Duty+Poly+Tubing
The 6 mil tube isn't really thick or strong enough, but I figure a
tripod type of arrangement should get me up to about 30-50ft. At
3cu-ft/min, my air compressor will take 20 minutes to pressurize to 2
atmospheres, so I'm currently looking into blowers and compressed air
bottles. I wanna try to raise a small yagi, but it most likely will
end up mooring an inverted-V.
There is a practical reason for all this as I wanna sell "emergency"
tower kits.
>a few field day's back (1988 or 1989 ) we had a 4sq inflatible
>vertical setup for 160 and 8 meters with 8 weather ballons in
>Humboldt countty.. Helium was to expensive ,, so we had a buddy that
>had a tank of hydrogen,,,
>
>worked good until sunday morning,, we head a 'pop' and on of the
>ballons broke, caught fire and we a a 'hot' vertical for 160
>
>No problems, the ballon was out before it landed, but what a trip,,
>the verticals worked great..
Nice work and great way to start a forest fire. Almost every year,
someone brings a balloon of some sorts to field day. Those are the
years when the wind is blowing, and the humidity is low enough to
produce really impressive sparks from the long wire. Every time,
someone's antenna tuner is sacrificed to the cause. The 160 meter
vertical magically became horizontal when the wind blew. This year,
nobody is going to bring a balloon, so I guess we won't have any wind.
Therefore, my inflatable tower might actually fly...err... work.
atec
>
>
> My goal is to create a city wide free alternative to the internet. Free
> meaning no connect fees. Each user would be required to buy his/her own
> router.Eventually it might actually connect to the Internet, but for now I'd
> be happy with a large intranet.
>
> It would be a hobbyist project. Anyone could get in for the price of the
> required hardware.
>
> Is this doable? Could it be done at prices that hobbyists would be willing
> to pay?
Well a number of area in Australia already do this ( similar anyway) ,
google brismesh or Sydneymesh .. have fun.
Bootstrap Bill
"atec" <ate...@XXXhotmail.com> wrote in message
news:42a3...@dnews.tpgi.com.au...
Thanks for the info. I was about to give up.
Bootstrap Bill
> It's difficult to justify even sharing the bandwidth when DSL at
> 1500/384kbits/sec now costs $15/month.
> http://promo.yahoo.com/sbc/
One problem. It isn't wireless.
With my network (if it works as I hope it does), you'd be able to roam
anywhere in the city with your palm pilot and make free voip calls to anyone
else on the network.
Jeff Liebermann
<william...@gmail.com> wrote:
>
>"Jeff Liebermann" <je...@comix.santa-cruz.ca.us> wrote in message
>news:rta4a1pgoj85f137b...@4ax.com...
>> It's difficult to justify even sharing the bandwidth when DSL at
>> 1500/384kbits/sec now costs $15/month.
>> http://promo.yahoo.com/sbc/
>
>One problem. It isn't wireless.
Most home users don't need wireless.
>With my network (if it works as I hope it does), you'd be able to roam
>anywhere in the city with your palm pilot and make free voip calls to anyone
>else on the network.
Once upon a time, I did some work with Metricom. They were into doing
the same thing. Users were expected to roam around the city with
their laptops (and later PDA's) while connected via (900MHz) wireless.
At one point, I inquired about the sales of replacement batteries for
the Ricochet radios. The NiMH batteries would last about 1-2 years.
It was evident that the battery sales were ridiculously low for the
number of units deployed. The implication hit me immediately that
these devices were not being used for roaming around, disconnected
from the wired world, but rather as an AC powered desktop modem
replacements to provide a full time internet connection. So much for
the un-tethered world.
The same thing happened with pocket calculators in the late 1960's.
Everyone predicted that calculators were going to be used for all
kinds of amazing things. My favorite is adding up your purchases at
the supermarket. I haven't seen anyone use a calculator in the market
for several years.
Another was the original concept of the laptop by companies like Grid.
Prior portables were "luggables" and too heavy to be considered truly
portable. Grid and Gavilan made the first laptops that could be
effectively transported. The advertising literature showed a business
executive (the only person that could afford the overpriced laptops of
the day) with the laptop on the hood of his luxury automobile on a job
site in the middle of nowhere. It was a grand picture of how portable
computing was going to revolutionize management. When I asked real
executives what they thought of the image, they informed me that they
had flunkeys to do their computing for them, and didn't want to be
bothered dealing with such mundane tasks as crunching numbers. So
much for portable computing.
Lots of other dumb wireless marketing examples on request.
So, if you have some illusions of supplying wireless connectivity to
the GUM (great unwashed masses), I strongly suggest you find a problem
worth solving with wireless, and then see if your solution fits the
problem and can justify the expense. Someone has to pay for the
system.
Not Me
"Bootstrap Bill"
<snip>
|
| With my network (if it works as I hope it does), you'd be able to roam
| anywhere in the city with your palm pilot and make free voip calls to
anyone
| else on the network.
How-to Build a CUWiN Metrix-based Node:
http://cuwireless.net/nodeconstruction?PHPSESSID=5fbbf1d210197accfc5f173150b0cc14
NewburyOpen.net is a movement that promotes the use of free WiFi for public
access and social justice in Boston and throughout the nation.
Not Me
"Bootstrap Bill"
| Who needs a tower?
|
| http://www.cnn.com/TECH/space/9808/07/solar.plane/
|
| Of course, it would cost far more than any group of hobbyists could afford
| to pay.
Sound like my sex life ... the real problem someone has to be constantly
playing with it to keeping it *up*
atec
see a couple of nodes and truthfully for the rabble we are its a great
little wan :_)
Richard Perkin
news:ogj4a1p3i7n87ic7q...@4ax.com:
> On 4 Jun 2005 00:07:54 GMT, Richard Perkin
> <f000n...@hotmail.com> wrote:
>>On a smaller scale to your vision, have a look at this:
>><http://www.daszeltonline.de/wlan/>
>>
>>If your German is not too good, look at the diagram and photos.
>
> http://freetranslation.paralink.com/
I've not seen that one before.
Personally I use BabelFish. Try this:
<http://world.altavista.com/babelfish/trurl_pagecontent?url=http%3A%
2F%2Fwww.daszeltonline.de%2Fwlan%2F&lp=de_en>
Like all machine translations it has some amusing side effects.
My German is not fluent, but I get by provided it's langsam
gesprochen :)
Kind regards
scharf...@gmail.com
outdoor antenna, except the person closest to the physical center. The
person in the center should get an omni-directional outdoor antenna.
Everyone should aim their directional antenna at the omni-directional
antenna. The person at the center could also install twelve access
points, with one 30 degree directional antenna each, and put them on
the roof for 360 degree coverage, but this will get expensive.
You will need to get Ethernet wireless adapters that have an external
antenna connector, i.e. Buffalo WLI2TX1G54. The reason for this is that
you cannot have a long wire from the wireless adapter, or router, to
the outdoor antenna, as the gain of the antenna is reduced with a long
wire. So you will connect the Ethernet Wireless adapter to the router
(or directly to the PC) with a long Ethernet cable, and place the
Ethernet Wireless adapter close to where the antenna will mount on the
outside of the house. You'll have to drill a hole in the wall for the
antenna wire, or maybe run in out a window.. There are antenna wire
extensions, but there are warnings that they reduce the gain by
0.4dB/foot.
You could always have the people on the ends, or outside, of the
radius, add a second access point that has a directional antenna to
another house on the outside of the next loop over, etc., and cover
large areas, though there is a limit as to how many people could share
a single DSL or cable modem connection,
If someone is connecting to their PC, rather than to a router in their
house, they can also get USB 2.0 access points that can accomodate an
external antenna, i.e. the Buffalo WLI2USB2G54, but the maximum length
of a USB 2.0 cable is much less than the maximum length of an Ethernet
cable. The plus side is that no power supply is necessary, and they are
much cheaper.
Not all wireless access points support external antennas, so choose
carfullly.
It will probably cost each person at least $125 for the Ethernet access
point and directional antenna.