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Wireless Ethernet Bridging at 200 Kilometers

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Anonymous
a b F Wireless
August 9, 2004 2:08:19 PM

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

Is there a way to do such a thing, either an amateur/poor (wo)man's
do-it-yourself approach, and/or a commercial system for say less than
$10,000 (excluding towers). With no intermediate relay points; and LOS or
possibly NLOS.

Of course, one could just do dial-up, or do VPN through an ISP
at both ends, but I am wondering if there is a not too
costly through-the-air option at this distance.
Anonymous
a b F Wireless
August 9, 2004 5:50:56 PM

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

carhore@yahoo.com (c hore) wrote:
>$10,000 (excluding towers). With no intermediate relay points; and LOS or
>possibly NLOS.

Well, you are going to require 2,000-foot towers on both ends, but
other than that it's LOS!

http://www.keytelemetering.com/9600_Antenna.htm
Anonymous
a b F Wireless
August 9, 2004 8:39:03 PM

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

"c hore" <carhore@yahoo.com> wrote in message
news:ca167c61.0408090908.132674d2@posting.google.com...
> Is there a way to do such a thing, either an amateur/poor (wo)man's
> do-it-yourself approach, and/or a commercial system for say less than
> $10,000 (excluding towers). With no intermediate relay points; and LOS or
> possibly NLOS.
>
> Of course, one could just do dial-up, or do VPN through an ISP
> at both ends, but I am wondering if there is a not too
> costly through-the-air option at this distance.

Really the best option in this case is to let the local telephone company
carry the infrastructure and buy their services. If you can get DSL at both
locations you can do the VPN thing, tunneling is another option, or even
with dial up, though it will be slow. Wireless is pretty much out as far as
the DIY stuff is concerned.
I have been told of someone that is using wireless at 100 miles which would
be about 160 KM or so but I haven't seen their setup and they are running
some large antennas and towers.
Since I work for an ISP I have some experience helping customers with this
type of stuff but it's usually contracted out.
AG
Related resources
Anonymous
a b F Wireless
August 9, 2004 11:38:20 PM

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

On Mon, 09 Aug 2004 13:50:56 -0400, William P.N. Smith wrote:

>carhore@yahoo.com (c hore) wrote:
>>$10,000 (excluding towers). With no intermediate relay points; and LOS or
>>possibly NLOS.
>
>Well, you are going to require 2,000-foot towers on both ends, but
>other than that it's LOS!
>
>http://www.keytelemetering.com/9600_Antenna.htm

just a thought, how long before we get SISPs (Satellite ISPs )
allowing us to bounce our signals straight up to space and back ?
Anonymous
a b F Wireless
August 9, 2004 11:49:09 PM

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

c hore wrote:

> Is there a way to do such a thing, either an amateur/poor (wo)man's
> do-it-yourself approach, and/or a commercial system for say less than
> $10,000 (excluding towers). With no intermediate relay points; and LOS or
> possibly NLOS.
>
> Of course, one could just do dial-up, or do VPN through an ISP
> at both ends, but I am wondering if there is a not too
> costly through-the-air option at this distance.

I don't believe it will work for this range. The longest range for a WLAN I
read about was somehwere around 190km (as far as I remember).
The stations had a direct view line (down from the mountains) and the
connetion was very unstable.

Thomas
Anonymous
a b F Wireless
August 9, 2004 11:56:10 PM

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

On 9 Aug 2004 10:08:19 -0700, carhore@yahoo.com (c hore) wrote:

>Is there a way to do such a thing, either an amateur/poor (wo)man's
>do-it-yourself approach, and/or a commercial system for say less than
>$10,000 (excluding towers). With no intermediate relay points; and LOS or
>possibly NLOS.

Sure. However, do you have line of sight? Last time I checked, the
earth is not flat. At 200km (125 miles) you'll need some rather
substantial towers to clear the earths curvature. My guess(tm) is
about 750ft high towers. Unless you live on a mountain, this is not
gonna work.

The record for the Wi-Fi shootout last week was 55 miles with no
amplfiers.
http://www.wifi-shootout.com
Note the size of the antennas. The all time record is 310km by
Alvarion from ground to a weather balloon.
http://www.alvarion.com/RunTime/CorpInf_30130.asp?fuf=2...
Note the 6 watts of power output.

It is possible to build a radio link that works over 200km, but there
are going to be some serious limitations. It will need to be at a
lower frequency, licensed by your favorite regulatory agency, and
limited in bandwidth to perhaps 4800 or 9600 baud. Not exactly high
speed, but it will work.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
a b F Wireless
August 10, 2004 12:16:14 AM

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

On Mon, 09 Aug 2004 19:38:20 +0100, sam1967@hetnet.nl wrote:

>On Mon, 09 Aug 2004 13:50:56 -0400, William P.N. Smith wrote:
>
>>carhore@yahoo.com (c hore) wrote:
>>>$10,000 (excluding towers). With no intermediate relay points; and LOS or
>>>possibly NLOS.
>>
>>Well, you are going to require 2,000-foot towers on both ends, but
>>other than that it's LOS!
>>
>>http://www.keytelemetering.com/9600_Antenna.htm
>
>just a thought, how long before we get SISPs (Satellite ISPs )
>allowing us to bounce our signals straight up to space and back ?
>
they already exist !

http://internet.about.com/library/aa_internet2_081302.h...
Anonymous
a b F Wireless
August 10, 2004 12:53:45 PM

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

On Mon, 09 Aug 2004 19:56:10 -0700, Jeff Liebermann
<jeffl@comix.santa-cruz.ca.us> wrote:

>On 9 Aug 2004 10:08:19 -0700, carhore@yahoo.com (c hore) wrote:
>
>>Is there a way to do such a thing, either an amateur/poor (wo)man's
>>do-it-yourself approach, and/or a commercial system for say less than
>>$10,000 (excluding towers). With no intermediate relay points; and LOS or
>>possibly NLOS.
>
>Sure. However, do you have line of sight? Last time I checked, the
>earth is not flat. At 200km (125 miles) you'll need some rather
>substantial towers to clear the earths curvature. My guess(tm) is
>about 750ft high towers. Unless you live on a mountain, this is not
>gonna work.
>
>The record for the Wi-Fi shootout last week was 55 miles with no
>amplfiers.
> http://www.wifi-shootout.com
>Note the size of the antennas. The all time record is 310km by
>Alvarion from ground to a weather balloon.
> http://www.alvarion.com/RunTime/CorpInf_30130.asp?fuf=2...
>Note the 6 watts of power output.
>
>It is possible to build a radio link that works over 200km, but there
>are going to be some serious limitations. It will need to be at a
>lower frequency, licensed by your favorite regulatory agency, and
>limited in bandwidth to perhaps 4800 or 9600 baud. Not exactly high
>speed, but it will work.

what about the satellite internet would that be any use to her ?
Anonymous
a b F Wireless
August 10, 2004 12:53:46 PM

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

On Tue, 10 Aug 2004 08:53:45 +0100, sam1967@hetnet.nl wrote:

>what about the satellite internet would that be any use to her ?

I only have limited 2nd hand experience with satellite internet.
Frankly, I don't know if satellite will work for an unspecified
application.

The big problem is always the huge latency.
http://www.satsig.net/latency.htm
It takes about 140 msec to go from the ground to the bird. A ping
requires two trips through the satellite so it will return about 560
msec minimum latency. That will kill anything in real time such as
VoIP.

Latency also limits the thruput because of the max window size of
64KBytes before stopping for an acknowledgement. For example, if you
can only send 64KBytes (512Kbits) and have a 1 second latency, then
your maximum thruput is:
512Kbits / 1 second latency = 512Kbits/sec.
This is why Starband, DirecPC, and DirecWay are intentionally limited
to about 400Kbits/sec. They could deliver more but you wouldn't be
able to use it.

The uplink is also incredibly slow. I think it's something like
16Kbits/sec. This is adequate for typical web surfing and email, but
forget it for anyting that requires outgoing bandwidth.

The various satellite internet providers have done some optimizing,
buffering, compression, cacheing, and tweaks to improve the situation,
but I suspect that they're only partially successful in dealing with
the aformentioned problems. For example, to use a satellite ISP with
a VPN has always been a problem because the cacheing mechanism breaks
down when faced with encrypted (and therefore random) data.
http://www.groundcontrol.com/turbo_vpn_001.htm
I have no clue if it actually works.

About a year ago, I helped setup (stood around sipping soda while
everyone else did the work) a DirecWay system on a mountain top radio
site. The plan was to use it for VoIP audio backhaul to expand a wide
area radio network. It worked well enough but the receiver voting
system could not handle the 1 second delay. So, it's being used for
telemetry and SCADA. Lacking other alternatives, it was good enough.

About 2.5 years ago, I scribbled a web page with alternative internet
access solutions for the San Francisco Bay area.
http://www.LearnByDestroying.com/nooze/wireless.htm
It's totally obsolete today, but does have some interesting items. I
included a "science fiction" section which includes schemes that
involve tethered balloons, airplanes flying donuts, weather balloon
repeaters, low earth orbiters, TV station rebroadcasters, FSO (free
space optics), and other oddities. Many are still in existance under
different names and investors, and may be found with Google.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
a b F Wireless
August 10, 2004 8:16:19 PM

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

On Tue, 10 Aug 2004 06:12:32 -0700, Jeff Liebermann
<jeffl@comix.santa-cruz.ca.us> wrote:

>On Tue, 10 Aug 2004 08:53:45 +0100, sam1967@hetnet.nl wrote:
>
>>what about the satellite internet would that be any use to her ?
>
>I only have limited 2nd hand experience with satellite internet.
>Frankly, I don't know if satellite will work for an unspecified
>application.
>
<snip very intriguing stuff>

do those satellite ISPs have servers orbiting up there ?
if so are they linux or windows ?
Anonymous
a b F Wireless
August 10, 2004 8:16:20 PM

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

On Tue, 10 Aug 2004 16:16:19 +0100, sam1967@hetnet.nl wrote:

>On Tue, 10 Aug 2004 06:12:32 -0700, Jeff Liebermann
><jeffl@comix.santa-cruz.ca.us> wrote:
>
>>On Tue, 10 Aug 2004 08:53:45 +0100, sam1967@hetnet.nl wrote:
>>
>>>what about the satellite internet would that be any use to her ?
>>
>>I only have limited 2nd hand experience with satellite internet.
>>Frankly, I don't know if satellite will work for an unspecified
>>application.
>>
><snip very intriguing stuff>

>do those satellite ISPs have servers orbiting up there ?
>if so are they linux or windows ?

I have no idea, but that won't stop me from venturing a guess(tm).
Since none of the geosynchronous birds have crashed, fallen out of the
sky, or turned blue, I'll guess that they're not using Windows. Since
none of them are enclosed in clear polycarbonate, I can also eliminate
Apple. However, I've noticed that no satellite or aerospace company
has published open source code to run a build it thyself satellite
transponder system, methinks Linux is not being used.

Ooops, I lied:
http://www.linuxworld.com.au/index.php/id;475140978;fp;16;fpid;0
There may soon be a penguin in orbit.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
August 11, 2004 2:15:02 AM

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

On Tue, 10 Aug 2004 06:12:32 -0700, Jeff Liebermann
<jeffl@comix.santa-cruz.ca.us> wrote:

<snip>
>It takes about 140 msec to go from the ground to the bird. A ping
>requires two trips through the satellite so it will return about 560
>msec minimum latency. That will kill anything in real time such as
>VoIP.

Correct. I use a business class Direcway (satellite system) for my internet
access.

Pinging www.google.akadns.net [216.239.41.104] with 32 bytes of data:

Reply from 216.239.41.104: bytes=32 time=651ms TTL=241
Reply from 216.239.41.104: bytes=32 time=703ms TTL=241
Reply from 216.239.41.104: bytes=32 time=631ms TTL=241
Reply from 216.239.41.104: bytes=32 time=660ms TTL=241

<snip>

>This is why Starband, DirecPC, and DirecWay are intentionally limited
>to about 400Kbits/sec. They could deliver more but you wouldn't be
>able to use it.

Incorrect. I achieve 2mbit/second+ download speeds at night, and 1mbit/second+
download speeds during the day.

>The uplink is also incredibly slow. I think it's something like
>16Kbits/sec. This is adequate for typical web surfing and email, but
>forget it for anyting that requires outgoing bandwidth.

Partially Incorrect. My max upload speed is 100kbits/second, but generally I
only receive that at night (I have the 0.98 meter dish and the more powerful
transmitter). During the day it averages in the 10-20kbit/second range.

<snip>
Anonymous
a b F Wireless
August 11, 2004 2:47:00 AM

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

On Tue, 10 Aug 2004 16:16:19 +0100, in alt.internet.wireless ,
sam1967@hetnet.nl wrote:

>On Tue, 10 Aug 2004 06:12:32 -0700, Jeff Liebermann
><jeffl@comix.santa-cruz.ca.us> wrote:
>
>>On Tue, 10 Aug 2004 08:53:45 +0100, sam1967@hetnet.nl wrote:
>>
>>>what about the satellite internet would that be any use to her ?
>>
>>I only have limited 2nd hand experience with satellite internet.
>>Frankly, I don't know if satellite will work for an unspecified
>>application.
>>
><snip very intriguing stuff>
>
>do those satellite ISPs have servers orbiting up there ?

The sats are relay stations, nothing more.

>if so are they linux or windows ?

fried, I should think, unless they were military grade hardware...

--
Mark McIntyre
CLC FAQ <http://www.eskimo.com/~scs/C-faq/top.html&gt;
CLC readme: <http://www.ungerhu.com/jxh/clc.welcome.txt&gt;


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups
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Anonymous
a b F Wireless
August 11, 2004 4:13:41 AM

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

On Tue, 10 Aug 2004 22:15:02 GMT, Beretta <invalid@invalid.org> wrote:

>Correct. I use a business class Direcway (satellite system) for my internet
>access.
>
>Pinging www.google.akadns.net [216.239.41.104] with 32 bytes of data:
>
>Reply from 216.239.41.104: bytes=32 time=651ms TTL=241
>Reply from 216.239.41.104: bytes=32 time=703ms TTL=241
>Reply from 216.239.41.104: bytes=32 time=631ms TTL=241
>Reply from 216.239.41.104: bytes=32 time=660ms TTL=241

Ok, so your theoretical maximum bandwidth is
512Kbits / 0.700sec = 731 kbits/sec

>>This is why Starband, DirecPC, and DirecWay are intentionally limited
>>to about 400Kbits/sec. They could deliver more but you wouldn't be
>>able to use it.

Well, DirecWay advertises 400-500Kbits/sec. I thought it was a hard
limit but apparently not.

>Incorrect. I achieve 2mbit/second+ download speeds at night, and 1mbit/second+
>download speeds during the day.

So much for theory. Is Directway doing any kind of compression? Is
the 2Mbits/sec download for pre-compressed files (i.e. zip, jpg, etc)?
Are there any hacks on your PC to handle large window sizes (RFC1323)
or selective ack's (RFC2018 or SACK)?

>>The uplink is also incredibly slow. I think it's something like
>>16Kbits/sec. This is adequate for typical web surfing and email, but
>>forget it for anyting that requires outgoing bandwidth.

>Partially Incorrect. My max upload speed is 100kbits/second, but generally I
>only receive that at night (I have the 0.98 meter dish and the more powerful
>transmitter). During the day it averages in the 10-20kbit/second range.

Well, DSLReports suggests 18-28Kbits/sec upload is typical.
http://www.broadbandreports.com/faq/2000
Also, the Direcway web pile shows the same speeds for home and
business use:
http://hns.getdway.com/packages.html
at 500Kbits/sec down and 50Kbits/sec up. However, the higher limit
before their "Fair Access Policy" feature stangles the download, for
business rate probably gives you a performance advantage.

When we were playing with the Direcway mountain top system, we were
doing all our testing during daylight working hours and were getting
an erratic 300-400Kbits/sec down, and about 16Kbits/sec up. I guess
things have improved somewhat.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
a b F Wireless
August 11, 2004 4:42:02 AM

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

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> Latency also limits the thruput because of the max window size of
> 64KBytes before stopping for an acknowledgement.

Is that the 64K tcp_windowsize max?
Doesn't that go away with RFC1323?
Long latency links benefit from an increase in the window size, if that's
the limit you're referring to.

I wonder what the settings are on a DirecWay installation.

http://www.grouplogic.com/Knowledge/index.cfm?fuseactio...
http://www.psc.edu/networking/perf_tune.html

> the aformentioned problems. For example, to use a satellite ISP with
> a VPN has always been a problem because the cacheing mechanism breaks
> down when faced with encrypted (and therefore random) data.

I thought the VPN broke down because the timing was deliberately very
tight, to try and avoid anyone spoofing the packets. The latency of the
satellite link is outside the allowable delay.

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
a b F Wireless
August 11, 2004 7:54:06 AM

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

On Wed, 11 Aug 2004 00:42:02 +0000 (UTC),
dold@WirelessXE.usenet.us.com wrote:

>Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>> Latency also limits the thruput because of the max window size of
>> 64KBytes before stopping for an acknowledgement.

>Is that the 64K tcp_windowsize max?

Yes, that's the one.

>Doesn't that go away with RFC1323?

Yes. It's the web servers that would be required to support RFC1323
as they are the ones sending the big blocks while the users Windoze
client is sending the acks. However, there's a huge difference in
available bandwidth between the satellite link and the terrestrial
connection between Direcway and the rest of the internet. The bulk of
the 700msec latency is concentrated between the users computah and the
Direcway routers. Only these routers and the clients computah need to
support RFC1323. Between the Direcway routers and the rest of the
internet, Direcway can run with a window size of 64KBytes because the
latency is much much lower. No need for every server on the internet
to support RFC1323.

>Long latency links benefit from an increase in the window size, if that's
>the limit you're referring to.
>
>I wonder what the settings are on a DirecWay installation.
>
>http://www.grouplogic.com/Knowledge/index.cfm?fuseactio...
>http://www.psc.edu/networking/perf_tune.html
>
>> the aformentioned problems. For example, to use a satellite ISP with
>> a VPN has always been a problem because the cacheing mechanism breaks
>> down when faced with encrypted (and therefore random) data.

>I thought the VPN broke down because the timing was deliberately very
>tight, to try and avoid anyone spoofing the packets. The latency of the
>satellite link is outside the allowable delay.

Nope. The problem I found is that the uplink bandwidth was
insufficient to keep the connection alive. Lots of timeouts,
disconnects, and hangs. Since the server was running Red Hate and
FreeS/WAN we disabled or drastically increased all the timeouts. That
let us maintain a connection, but the download thruput was something
like 30Kbits/sec. Almost all the upstream traffic was VPN overhead.
I gave up early (before sanity loss) and simply setup an SSH login
using Putty as a client. That worked well enough, but not much
faster. A real Linux expert was dragged to the mountain top to make
it work. He burned a week and also gave up. There are plenty of
"enhanced" VPN over satellite solutions, but I have no clue how (or
if) they work.
http://www.skycasters.com/broadband-satellite-vpn/index...
http://www.futureviz.com/vpn/

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
August 11, 2004 8:17:13 AM

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

On Wed, 11 Aug 2004 00:13:41 GMT, Jeff Liebermann <jeffl@comix.santa-cruz.ca.us>
wrote:

<snip>
>
>Well, DirecWay advertises 400-500Kbits/sec. I thought it was a hard
>limit but apparently not.

Actually, for the business class systems, the advertise 1mbit downloads. I have
found that to be a very conservative estimate on thier part. Of course, it could
well be that I am on an optimum satellite. I know they contract out for some
(they have 40 available for inet access)


>>Incorrect. I achieve 2mbit/second+ download speeds at night, and 1mbit/second+
>>download speeds during the day.
>
>So much for theory. Is Directway doing any kind of compression? Is
>the 2Mbits/sec download for pre-compressed files (i.e. zip, jpg, etc)?
>Are there any hacks on your PC to handle large window sizes (RFC1323)
>or selective ack's (RFC2018 or SACK)?

I know that webpages are compressed, not sure about other stuff. I ran a quick
test today on a 10mb file I generated from /dev/urandom (linux) on a cololcated
box I have and since random data doesn't compress well, and I was able to
achieve the 1mbit speed I usually get, I'd have to rule out compression being a
factor. And no, all my settings are standard windows and linux settings. No
hacks, no tweaks.

I've got the satellite modem connected to a Senao 2611-CB3+ (802.11b) running in
AP mode transmitting the signal about 300 meters to a Linksys WAP54G running in
client mode, which is in turn plugged into a 5 port switch. (lots of trees
around my house, had to setup the dish a bit away). I'm using high gain antennas
and am no doubt exceeding FCC limits, but as I am in a secluded valley.....

Your stats may all be true for the homeuser systems. I don't know. But the
business class system is performing really well. Granted, $129/month is a lot,
but all you gotta do is get 3 or 4 people to share it, and it's not so bad.
(That's what I did) Since Hughes/Direcway advertises it as "designed for up to 5
concurrent users", I figured sharing wasn't unethical.
!