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Wanted - 45 Mile Wireless Broadband?
Slashbaby asks: "I am a net admin for a school division that doesn't have broadband Internet. We are a rural school division, so we don't even have a provider in any of our towns. What I am looking for is a way to get highspeed Internet access into our division through either RF or microwave. There is a city about 45 miles away, (max. distance) that has ISP's that would be willing to sell us bandwidth if we can find a way to get it the 45 miles to the schools."
"What I am looking for is either companies or websites that deal with this kind of technology. I have no idea what to really look for, so any help ideas would be appreciated. Our budget for this project would be ~$125 000 CND ($80 000 USD).
We are currently using Direct PC satellite (which is NOT broadband) Unfortunately, they are dropping us in 2003...they are dropping service for rural communities in order to expand service for government funded projects."
Try a solution based on a form of 802.11, or it's variants. Find a suitably high place in the city to mount a directional antenna on, point it at your school, go about 10 miles, install an 802.11 acces point in some friendly location, add more directional antennas. You'd probably run up to $10k getting the proper communications equipment and such, and you'd need a PC at the first of the hubs to be providing the gateway (*Nix or 2K Server so it won't crash too much) It might work or it might not. There are many communities that are providing 802.11(x) service for their entire city, but I don't think it's ever been taken past a city before.
JKoebel
My school district used to be in the same situation. We used Intellicom's VSAT technology.
http://www.intellicom.net/kids.htm
45 miles is a pretty long haul for RF, given as other posters have remarked, the Fresnel zone, line of sight, and - from what I have been told -- the the curvature of the earth at those distances.
I administer a WWAN for my employer. We use Solectek Skyway wireless Point to Point bridges/routers. These units operate at 11mbps in the 2.4Ghz spectrum. I like these units alot, they are well made (NEMA compliant) and perform very well (~20ms latency on my 90 mile roundtrip network). They do not use 802.11b due to some the inherent problems with that standard. Their WCOPP RF protocol is based on HDLC, and their bandwidth managment is top notch.
Their maximum rated distance is 30 miles. My longest link currently is 18 miles (line of sight) and works great. While you may not be able to dp 45 miles with one link, it might be possible to operate a repeater site off of some radio tower between you and the city. I have 2 such sites, due to line of site concerns.
Good luck!
How about satellite?
I know that ping times are a little crappy, and if you want to do any hosting you'd best forget about it and all, but it's not too bad a solution.
Down here in Australia, we've got a real problem with rural schools. 45 miles is nothing, some face distances of hundereds of miles to the nearest populus. Telstra, our major carrier tend to pitch the satellite option to our rural users quite heavily.
I work for a regional school, and although we aren't far from a small population, we still don't have access to DSL or anything similar, so we use a Sat. connection. It isn't perfect, but it does the job where the kids are concerned. It serves 150 desktops without any real difficulty, and with very little downtime due to the satellite itself (some due to the people running it though).
I'm sure there must be some Sat. options available in other countries (after all our uplink is in the U.S.). You might want to give it a try!
"How much truth can advertising buy?" - iNsuRge - AK47
Have you considered using multilink ppp over modem connections? Assuming you can get a 56k modem connection in your area, buy 4 modems and get an account with an ISP that supports multilink and always on connections. Cost shouldn't be too bad: 4 lines * $20 + $50 ISP account(???) = $130 a month for approx 200kbps. Cheaper than a T1 and works anywhere with decent analog phone service. Add more modems if you need more bandwidth.
From here:
Northern Lights School Division No. 69
Project brings the internet to rural school division
Northern Lights School Division defied conventional wisdom to bring the world to the desktop of over 6,700 students and 700 staff in 25 schools. Using Wi-LAN technology the jurisdiction established the world's biggest wireless education system in both geographical area (5,714 square miles) and number of sites. It cost them $650,000.
The project has been recognized for its innovation and successful implementation both within the educational community and the industry. ASBO International awarded project manager Gary Krawchuk the Pinnacle Award for Excellence, making him the first Canadian to receive this prestigious award.
For more information contact Ed Wittchen,
Superintendent, at 1.780.826.3145.
Metamuscle.com - News in the Iro
Depending on who your RBOC/Telco is, you might want to consider frame relay from them. I used to run a small ISP in Oklahoma, and Southwestern Bell has *no mileage charges* on their frame relay service.
We used Intermedia for our primary pipe, but for redundancy, we got a second pipe from Southwestern Bell Internet Services. 1.5mbps, 64 IP addresses, DNS provided by them if we wanted to use it (which we didn't). They used Williams for their upstream backbone, which performed rather decent. All for only about $500/month, again with no mileage or loop charges.
Most likely Pacific Bell and the former Ameritech have similar pricing since DBC has borged them both.
A quick bit of background.
I am co-owner of a tech engineering company in the mid-west. We specialize in 4 areas, Cisco, Linux, Medical IT and last but not least wireless network design (LAN, WAN and Long Haul).
We had a customer that needed an interum solution (something to last them about 10 months until another means of connectivity came available). It had to be inexpensive, relatively fast, and wireless. We used FHSS gear to accomplish our task (Proxim RangeLAN2 to be exact). Our reasons were many, but I won't go in to that here. I will say forget about 802.11b for this (and for any serious wireless tasks other than LANs). We used two Proxim 7521-05 access points (the XR series as it outputs at 500mW as opposed to the 7520 which outputs at 100mW). As someone alluded to earlier, you have to have Fresnel clearence (ie cooperative geography). You have to know how to do a path survey, and you have to do one methodically at this kind of distance.
Let's assume that for you "task at hand" you can gain Fresnel Clearence and you want to do this. Since you are in Canada, you have to know your output power limitations, here in the US you cannot use high-gain antenna's with the 500mW AP's, unless you attenuate the signal before it reaches the antenna to reduce the output power to legal limits (and in the Carribean where we also do a lot of work, no one gives a rats butt what the law says). Not a problem for this type of thing, as normally the cable length from the ap to the Antenna on top of the tower is sufficient to reduce signal strength. Anyway, a couple of 21dBi or 23dBi parabolics, a couple of AP's (one in master mode, one in station mode), some cable and either your own tower or access to a tower on each end. Keep in mind, you can always use a repeater (passive or active) to clear obstacles in the middle, or to zig-zag as needed. Let's look at some dollar figures.
7521-05s normally retail for about $1,100 bucks. We are currently buying them for $189 from a place that bought out an ISP that went belley up. They are brand new in OEM packaging. Their address is www.imsales.com. So...
$400 for two APs
$800 for two good quality Parabolic Antenna'
$800 for excellent quality cable
$500 for two polyphaser lightening arrestors
Who knows for towers.
You got a long way to go before you reach 80 G's.
Now, the down sides. First, the speeds aren't going to be stupendous. You'll get between 800Kbps and 1Mbps. Still, not bad. The task of path surveying is not for the inexperienced. It requires lots-o-experience and knowhow, but there is certainly someone in your area that can do it (ask the local cell phone company who they use). Finally, antenna aiming is critical.
There are some other technologies that could get you higher speeds at a higher cost, but still unlicensed. Again, if you want to discuss this in more detail, e-mail me (rindeee@yahoo.com)
Anyway, I hope this helps. I will gladly give you more specifics, debate the virtues of various wireless technologies for this aplication, etc via e-mail at rindeee@yahoo.com. Be glad to help you accomplish your task...I think you will find it quite pleasing in the end.
PS. "Catagory 3" 802.11a (there are three classes of 802.11a the third intended for longer distance point to point) may be workable for this, but it's not on the market yet, so I don't know. The 2.4GHz stuff (Proxim RL2) is nice as the lower frequency than 802.11a (which runs at 5.8xGHz) is a bit more resiliant and has much better propegation over long distances.
For more info look at www.proxim.com and go from there.
You will need a clear fresnel zone of around 300 feet (back of the envelope figures) above the tallest obstruction in the path. So you are probably talking about a 400+ foot tower, or something like a 150 foot tower on a 300 foot hillside (cheaper).
A 45 mile link will be hard to align properly, you will want to hire professionals. Cell phone companies use this kind of gear and go these distances regularly, for their cell-to-cell backhauls.
Preface: I'm amazed at how poorly Slashdotters read the question. The post is about a 45 mile hop in rural Canada -- this is not the usual suburban nerd's home connection. No FCC, no RBOCs, and no, you can't just trench 45 miles of fiber optics for C$125k. (That's about what one mile of urban trenching costs, or maybe ten miles of rural Ditch-Witch burial.)
This type of application can, I'm sure even in Canada, use licensed point-to-point microwave. This allows lots higher power than 802.11 (forget the "b" which means higher speeds for even shorter distances). Typical rule-of-thumb is that frequencies under 10 GHz can go up to 30 miles (okay, say 45 km) on a single hop, if you can get line of sight. The site in question might need a repeater along the way. The terrain is all-important.
It probably is possible to get some microwave radios on that budget, though a repeater would possibly blow the limit. Harris, for instance, has a good selection, and a free program, Starlink, on their web site, which does path calculations for various radio - antenna combinations. (You can source the radios elsewhere, but Starlink is obviously geared to match Harris' own radios.) These would probably deliver 3 to 45 Mbps, depending on the radio in question. Industry Canada (which regulates spectrum matters) would probably be able to point you in the right direction for licensing and frequency/path coordination.
Propagation characteristics differ depending on the frequency involved. Energy density will determine whether or not a signal is degraded enough to detect it or not.
Line of sight is not a good rule of thumb for RF propagation- for some things it's a good rule, for others it's only a good determinant of the maximum possible range.
RF is an interesting beast, one in which at one frequency, you're absorbed by the media, in another you're scattered by the same. Sometimes reflection comes into play and the signal bounces all over the place getting where you don't expect it. Sometimes the signal penetrates some media and goes further than you'd normally expect it to. Sometimes the signal hugs the earth and follows it's curvature to some extent (Which is where people get the thinking of line-of-site from- some signals bend some don't.).
Low frequency can be propagated through water and rock. High frequency can't. Low frequency propagates along the curvature of the earth. High frequency propagates along straight lines from the emitter source.
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