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Wanted - 45 Mile Wireless Broadband? 409

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."

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Wanted - 45 Mile Wireless Broadband?

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  • If you get phone service out there, check into your local company.. maybe they can contract out with the big boys to provide you with a bunch of DSL trunks, which will get you some good bandwidth.
  • Just buy... (Score:2, Funny)

    by Nutt ( 106868 )
    A whole lotta cable :)
    Too bad bandwidth through power lines hasn't come out yet. It probably woulda come in handy now.
    • ...is painfully slow and noisy. Until proven otherwise, I'd imagine internet access through power lines would be the same. There's just too much noise from sudden power drains (such as applicances and factory machines) or surges. The power grid was built to carry power, not data, and it is singularly unsuited to the latter role.
    • Try asking the power company.

      My uncle works for Minnesota Power, and electric utility in northern Minnesota. Apparently they're doing a bit of a side business by selling excess capacity in their microwave relay system that is used to control and monitor their grid. They've also started running fiber with their transmission lines that they've installed in the last few years to expand their broadband capability.

  • hmmmm, good luck (Score:1, Informative)

    by gladbach ( 527602 )
    I imagine that would be prohibitably expensive, esp for a school district.
    • Re:hmmmm, good luck (Score:2, Informative)

      by dangermouse ( 2242 )
      If I had any mod points, I'd drop a plus on this one.

      Too bad there isn't a "+1, this guy's right, you're screwed" for Ask Slashdot posts.

  • by Sp00nMan ( 199816 ) on Sunday October 14, 2001 @05:23PM (#2428215) Journal
    I heard Iridium phones are going cheap.. How about purchasing the whole smear and having satellite modems ;)
  • 802.11(b) (Score:5, Informative)

    by man_ls ( 248470 ) on Sunday October 14, 2001 @05:24PM (#2428218)
    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
    • Re:802.11(b) (Score:4, Informative)

      by mystik ( 38627 ) on Sunday October 14, 2001 @05:37PM (#2428281) Homepage Journal
      IIRC (i could be wrong) 802.11b will automatically figure out overlapping zones, and repeat accordingly -- It might be a few hops inbetween, but the ISP might be willing to offer service to anyone in between who just happens to be near one of the APs. The ISP may want to give you somewhat of a discount if both parties agree to put some money into the project ...
    • Re:802.11(b) (Score:4, Insightful)

      by masteroveride ( 459247 ) on Sunday October 14, 2001 @05:37PM (#2428282)
      The only problem about 802.11 is its security. I mean all I would need is my laptop, some software and a wireless card and I could read every e-mail or web page visited.
    • in spite of high karma score, this really isn't an informative solution.

      802.11 at legal limits /may/ work up to 10 miles (terrain and a lot of other factors pending - we've shot it over 24 miles in an amateur test so we can exceed fcc regs on part 15, but it's not usable for non-amateur purposes at that amplification/gain and certainly wasn't terribly reliable either - crc and duplicate frame errors up the wazoo). using that approach, you'll need site acquisition in 8 locations. your isp probably doesn't have a suitable tower for the run, so you have to count the uplink, but you may be able to shoot the last run to the school without a site cost. remember, 10-mile shots need clearance and that means a good amount of height - you're not going to stick these anywhere less than a good 50' over the treeline (trees eat 2.4 GHz).

      8 802.11 line-of-sight pairs using bridges, high gain dishes, etc. runs at least $5K a pair bare bones (including your cabling, nema boxes, etc.), not including the tower, site acquisition, price of installation, etc. factoring those items in, you might double or triple the equipment number. let's say no less than $10K per site x 8 = $80K.

      while we're just slightly over the $75K budget, we've constructed a sloppy network that has 8 fail points and terminates into a city - very likely a noisy zone for 2.4 GHz (most are nearly unusable for this sort of link with any level of quality). and you're probably getting at best a 1 Mbps link.

      a better solution is two 35-mile engineered links using licensed 6 GHz gear (and if need be, use a 5.8 GHz link from the city tower to the ISP's facility). this will mean two 6 GHz links and 1 5.8 GHz link: $32K + $32K + $10K = $74K total (factoring less sites and less labor included). we make the budget and have 10 Mbps of thruput, though we need to have someone competent (aka "rf professional") do the link since we're dealing with licensed frequencies, permitting, towers, etc. try hunting thru your wireless isp players, since some of us like working with schools and occasionally work at a serious discount to make things happen for them.

      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.

      Wow... and that deserves a '5' score? Sorry... 802.11 point-to-point has been done for several years in these parts, and we're usually behind the times regionally. Would I rely upon it? No... not unless I was in BFE running a link between two farms with nothing 2.4 GHz nearby. Or did you mean 2.4 has never been out of the city? Huh? I run it on my 50-acre farm and walk around with my ipaq all over the place. The poster sounds like he/she's never been off of Manhatten in his/her life!

      *scoove*
  • I suppose you could offer to give residential homes between you and the city free access to your broadband pipeline as long as they set up equipment to act as a wireless relay. You supply/(pay for) the bandwidth and access..and willing participants will set up the equipment.

  • Fresnel Zone (Score:5, Interesting)

    by Jason Straight ( 58248 ) on Sunday October 14, 2001 @05:24PM (#2428222) Homepage
    Your biggest problem will be overcoming the fresnel zone. Most wireless requires radio line of site, which means there can be no obstructions. The fresnel zone is actually the eliptical path that a radio wave takes from one point to the next - for a 45 mile link you would need ungodly clearance between the 2 points. To calculate the fresnel zone and other requirements try going to www.ydi.com and use their online calculators.
    • Transmit it in AM (or whatever freq you can do this in) and bounce it off the atmosphere all around the planet :)
      • HF radio waves bounce off the ionosphere, not the atmosphere, though some would argue that the former is merely a subset of the latter.
  • If you do, some kind of microwave system might work. If you don't have line of sight (or can arrange for a series of relays), you are probably out of luck.
  • by OmegaDan ( 101255 ) on Sunday October 14, 2001 @05:25PM (#2428229) Homepage
    Microwave. Our local school district has microwave on the top of every school (of course we live in a valley and theres only 1 elevator in the entire town. So line of sight isn't too difficult). Althought I personally have no experience with the stuff :)

    BTW, whats wrong with two way dish ?

    • It's about a 128K download speed and a 50-60K upload speed. While most people would consider that as at least "sort of good" in comparison to their 56Ks, those speeds become really, really crappy when you have kids on fifty to sixty different computers in the school at a time wildly downloading things, including big video files as video aids and shockwave games during lunch hours. Just think about it. With about sixty kids on at a time, that's only 2K per kid. You'd practically have to start downloading a page a day ahead at that rate.
      • ok, so, buy 5 dishes and a load balancer. that should be what, 250 - 500$ a month ? your school probably spends more on toilet paper

        • Satalite is just nasty. I had one for 5 months while I was playing nature-boy. You're better off with 30 modems, shotgunning them so you have 15 fast connections with drastically reduced ping times. I dunno how big a school this is... but if we assume you just need 15 the price for service is about $7(if you're smart about your ISP)x30 = $210 a month. Plus the cost of shotgun modems.

          • You need to do your homework. There are satellite providers that offer 1.5 mb forward with 512k reverse channels. They also offer guaranteed QoS. These are very different from the over-subscribed consumer services. These services work very nicely.
          • If you can get 30 phone lines into the school, why couldn't you get a leased line from the telco to the city? 45 miles is a long way but it's not that big a deal with repeaters.
  • $80,000 should be enough for 45 miles of fiber...
    • Re:Fiber (Score:2, Informative)

      by freebase ( 83667 )
      Fiber installation typically runs $15K-$90K per fiber mile, if one already has the right of ways.

      The fiber itself is cheap; the expensive part is installation which is highly labor intensive, even today. Add in the insurance installers have to have to cover cable cuts made when they run their directional boring machine through someone's cable, and it's obviously not a project you'd want to take on without some kind of co-op with city/regional government.
    • Re:Fiber (Score:2, Informative)

      by John Hasler ( 414242 )
      This guy is in rural Canada, not downtown LA.
      Rural fiber gets plowed in. Two fiber cables cross my land, and I watched both go in. The 'dozers laid cable at the rate of about 1/2 mile per hour and there isn't a manhole every mile, let alone every 1000 feet.
  • Range Reality Check (Score:5, Interesting)

    by zobo ( 60591 ) on Sunday October 14, 2001 @05:33PM (#2428263)
    Here [oreillynet.com] is an article called "Range Reality Check" that looks at the range from a purely physical perspective. The conclusion drawn by the author, one of the NoCat [nocat.net] folks, is that
    "...your antennas would have to be at least 104 feet above the surrounding terrain, separated by 25 miles, pointed directly at the ground 12.5 miles away, with no intervening ground clutter."
    So, in theory the original poster could achieve a range of ~50 miles with a repeater station (PC with two 802.11b cards) at the midpoint, 4 high-gain directional antennas, etc.
  • Field day (Score:5, Funny)

    by JanneM ( 7445 ) on Sunday October 14, 2001 @05:35PM (#2428271) Homepage
    Have a company sponsor you with cat-5 cabling and cable pipes. Then declare a "Plant A Cable" field day in the entire district, spread the kids out evenly along that 45 mile stretch with shovels and pickaxes, and let them dig! Or you could have a chain-gang-themed masquerade, and have them in striped shirts and fake manacles, with a price to the class with the best costumes.

    Or maybe not.

    /Janne
    • That makes no sense since you'd have to have hundreds of switches just to make it work. The latency and signal degredation would be horrendous. The only way you could do it via land is with fiber, preferably single mode. cheap cat5 and commodity equipment isn't good enough for this application.
    • Re:Field day (Score:2, Interesting)

      by jjshoe ( 410772 )
      in a more seriousness, you could easily get donated cat5 as well as pvc, rent a trencher, and go for it, if there is a strait shot road you could do it in a few weeks easily, if you did only a mile a day you would make it pretty far.

      but in another aspect, when a local elementry school went fibre optic, the armed forces came in and did it for the experience. perhaps this is something you can look in to?

      and in a much more uprofesional method, whats the range on dry lines?
    • Re:Field day (Score:3, Informative)

      by pongo000 ( 97357 )
      Maybe so...the West Texas town of Throckmorton laid 15 miles of water line in 15 days [awwa.org], mostly through volunteer labor. Why not some fiber optics? Seems like all you'd need is a smaller ditch.
    • by Monkeyman334 ( 205694 ) on Sunday October 14, 2001 @07:40PM (#2428694)
      If you really wanted to abuse the children, you should have them carry the packets back and forth.
    • Re:Field day (Score:3, Insightful)

      by Kallahar ( 227430 )
      CAT5 would most definately NOT work over 45 miles. the maximum cable length without using a repeater is a few thousand feet (total, including all splits)

      I agree that fiber would be the only way, and you mights still need powered repeaters along the way, but you may be able to power these with solar arrays at the spot.

  • by Adam J. Richter ( 17693 ) on Sunday October 14, 2001 @05:40PM (#2428300)
    I don't know what the law is in Canada about 802.11b wireless ethernet, but people do make line of sight point-to-point 802.11b links with dish antennas on both ends that are as long as 20+ miles. I understand that Linksys WAP11 access point (US$200) can be configured as a repeater, as can some Cisco Aeronet unit that costs US$1k. Of course, when you include the antennas, housing, professional design and installation, the cost of making these repeater stations will go way up, but still nowhere near US$80k.
  • Satellite (Score:4, Informative)

    by bstory ( 89087 ) on Sunday October 14, 2001 @05:43PM (#2428311) Homepage
    My school district used to be in the same situation. We used Intellicom's VSAT technology.
    http://www.intellicom.net/kids.htm
  • A suggestion (Score:5, Informative)

    by Ranc0r ( 12107 ) on Sunday October 14, 2001 @05:46PM (#2428329)

    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 [solectek.com] 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!

  • See Reach Out and Touch Someone [pbs.org] and some more followups in Cringely/Old Hat [pbs.org]. Admittedly, he used 802.11b wireless for less than 10 miles, but maybe you can extend the technology somehow.

    One followup which might be of interest is the suggestion to become the broadband supplier for your town: Roll Your Own: Not Only Can You Do Your Own DSL, Here's How to Become a Broadband Tycoon at the Same Time [pbs.org] -- if you could do that and get enough 802.11b customers locally (meaning no wires to string), you could justify some up-front costs.

    HTH
  • by schmaltz ( 70977 ) on Sunday October 14, 2001 @05:48PM (#2428340)
    but the distance wasn't so far, only 10km. He used telescopes to find a neighbor who was close enough to telco for DSL (Cringely wasn't), then hooked the neighbor up for free and mounted 21dB-gain directional Yagi antennas.

    The story's an interesting read [pbs.org].
    • This was a very interesting article. A couple of sticking points come to mind immediately. I dunno, maybe I'm a pessimist.

      - What if the guy with the DSL connection has his phone and/or electric service cut off for some reason?

      - What if, aided by his newfound bandwidth, becomes hopelessly addicted to multimedia porn newsgroups and sucks up all the bandwidth?

      - What if they guy moves and is a jerk and takes the Airport basestation and other equipment with him? Even though setting up the shared connection is not technically illegal, it might be a pain to press charges in such a case.

  • Form a co-op (Score:5, Insightful)

    by jhubbard ( 4916 ) on Sunday October 14, 2001 @05:57PM (#2428382) Homepage

    Why doesn't the local communities get together and form a co-op? The school system would take the lead on this since they would benefit first but the rest of the members would benefit.

    If your system is anything like where I grew up, we had small schools for each of the communities. Why not take a room from each of the schools and turn it into the local pop for the service. If you've got a line of sight from each of the schools or could get access to a point where you could relay it, then you wouldn't have to worry about using T1's to connect each of the locations.

    The co-op would sell access to the Internet and since they're the only game in town there's no competition.

    The school system would get deep discount since they're providing the space and power. But, setup a non-profit to run it and make them responsible.

    Of course they'll be some interesting political hurdles to jump but hey that's what makes life so great.

    If you live in Virginia there is a state program to get deep discounts called Virginia Link [valink.org]. They did have some really nice pricing on T1s and installation. James

  • Satellite? (Score:4, Informative)

    by Halster ( 34667 ) <haldouglas@gm[ ].com ['ail' in gap]> on Sunday October 14, 2001 @05:59PM (#2428387) Homepage
    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!
  • by mini me ( 132455 ) on Sunday October 14, 2001 @06:00PM (#2428390)
    The high school I used to attend had wireless broadband years ago (well probably 5 or 6 years ago anyway).

    A little poking around on the net brought me to this site [packetworks.net] which explains all the details of the install at my school and the other schools in the board. You might want to check out that site for some ideas anyway.
  • Relay's (Score:2, Interesting)

    by NotoriousQ ( 457789 )
    If your area has cell phone towers, then radio relays can cannect you. (It uses those microwave dishes that are on each cell tower, thus you do not have to set up a single huge dish up high.) I do not know the price, but it has been the way my company has linked remote offices in the mountains. I heard it is pricey for a subscription, but bearable. It is also not too fast, but it will be faster than 56k, and is essentially your network...you set it up, they maintain the dishes. BUT You will also have to deal with telco BS.

    I would say try getting T1 if you can
  • Porsche-net (Score:2, Funny)

    by Anonymous Coward
    Buy yourself a nice car for $100,000 CDN and a CD burner and offer to drive CD's from the city to your town.

    :-)

    You will get better range and lower latency than sneaker-net.
  • Long shot 802.11 (Score:3, Informative)

    by Destroyer_of_worlds ( 528318 ) on Sunday October 14, 2001 @06:08PM (#2428423)
    Someone mentioned the article O'reilly had on a long shot 802.11b connection. It can be found here:
    • http://www.oreillynet.com/pub/a/wireless/2001/05 /0 3/longshot.html
    It would be interesting to see if they could pull this off with repeater stations, the only problem being cost for putting up the antenas needed. Not sure how much that would cost, but I'm guessing a lot!
  • multilink ppp (Score:5, Informative)

    by ibex42 ( 135204 ) on Sunday October 14, 2001 @06:10PM (#2428429)
    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.
    • Re:multilink ppp (Score:3, Insightful)

      by spudnic ( 32107 )
      I'm not sure about Canada, but in most rural parts of America a call to a city 45 miles away would be considered long distance.

      Considering a rate of 7 cents a minute for 4 lines on from 7am to 4pm, you're looking at about $151 a day in long distance bills.

      I'm sure he could get a T1 or some other service that would not only blow it away in quality, but also in price.
    • Re:multilink ppp (Score:3, Insightful)

      by zerocool^ ( 112121 )
      that's not gonna work from a bandwidth standpoint. You're forgetting Kbps versus kbps - while that would be over 200kbps, think of it this way:

      On a typical 56K modem you get between 4.5 and 6 K a second (that's Kbps). So with 4 modems, you'd get somewhere between 18 and 30 Kbps. Not really fantastic bandwidth for even one computer, much less splitting up amoung 40 or 50.

      Add to that the fact that your upload stream would be 28.8 X 4, or about 10-15 K a second, and you have a picture of why this wouldn't work. $130 a month for 30K max down and 15K max up is no bargain, and not sutable for splitting into a school network.

      ~Z
  • what happened to PCDirect? High-speed down,
    modem uplink, maybe twin modem uplink. Should be plenty of bandwidth for a school, unless you're producing amateur video.
  • I think probably the best chance you have is to set up two or three repeaters in between your school and the city. Someone earlier mentioned that you could go 25 miles, but with a very tall antenna (100 feet is very tall for an amateur project, IMHO). Hops of 10-15 miles would be easier.

    Then again, there may already be some tall structures or antennas in your area. If there's a radio or TV broadcast antenna in between the two cities, it might be a good idea to ask them if they would do it. Of course, these folks probably actually talk to the FCC on a moderately regular basis, so they might be somewhat concerned about helping in this way..

    Cell phone towers might be good candidates for the several-hop idea..
  • by kalinh ( 167661 ) on Sunday October 14, 2001 @06:35PM (#2428519) Homepage
    I'm not sure of all the details on this implementation, but the Northern Lights School district in northern Alberta, Canada did something similar. I tried to find some information for you, and only have time to dig this up, but there is some contact information, and further digging should reveal more.

    From here [asba.ab.ca]:

    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.

  • Two way Satellite (Score:3, Interesting)

    by certsoft ( 442059 ) on Sunday October 14, 2001 @06:36PM (#2428522) Homepage
    Have you tried www.tachyon.com? They have a number of different plans depending on the bandwidth you require. $80000 would support this type of system for many years.

    I've been using a tachyon system for over a year and I find it works just fine for web surfing, email, FTP uploads, etc. May not be good for gaming, but students are supposed to be doing real work :)

  • Consider Frame Relay (Score:5, Informative)

    by Noxxus ( 259942 ) <noxxus@tripflare.com> on Sunday October 14, 2001 @06:37PM (#2428525) Homepage
    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.
    • Yeah. i tend to agree. Mileage charges or not, either getting a ptp T1 or a framerelay line is probably the way you want to go.

      Many people are suggesting exotic ideas like making 802.11 antennae out of pringles cans and such, but I can almost assure you that's going to be a bad idea. When something catastrophic happens, ie, rain, or wind, it's going to be your (now wet from rain) ass going out there trying to adjust your pringles can so that it points the right direction again. And your (this time dry) ass will also be on the line as your administrators ask why their email goes down everytime it rains or gets windy. I'm assuming that at your job you have better things to do than this.

      Most LECs (or if you're lucky you can find a longhaul carrier that'll do it) have very decent turnaround times on fixing circuits when they go down (which btw is also very rare with t1s and/or framerelay).

      Frankly i'm amazed your ISP isn't helping you more with this. They have a LEC reseller that can easily price this out these land-based options for you, if they won't do this for you it's time to find another ISP. Also you might want to look at buying directly from the Tier1s, often they'll be able to undercut a local/regional ISP just because of their longhaul ties and unusual POPs so they can save large amounts of money on linecharge.
  • by Anonymous Coward on Sunday October 14, 2001 @07:10PM (#2428613)
    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.
    • I was just wondering if it's possible to bond these connections together using multiple antennae and wireless transceivers on the same towers?

      Would the restriction on power output be calculated on a per antenna or a per installation basis?

  • Netopia has a multiple idsl unit, upto 576Kbps per unit (4x144kbps). Get 3 of these and combine the bandwidth for 1728kbps worth of bandwidth.

    $1200 (3x) Netopia R3100-I [netopia.com]
    $600 (12x) ISDN line
    $2500 ISP data charge
  • by nowt ( 230214 ) on Sunday October 14, 2001 @07:59PM (#2428746)
    Watch those packets fly with http://www.blug.linux.no/rfc1149/

    Enjoy!

  • I don't see why not! (Score:3, Informative)

    by funky womble ( 518255 ) on Sunday October 14, 2001 @08:01PM (#2428751)
    Of course the exact setup will depend on factors such as terrain and which licensing restrictions you are subject to, but providing you can find locations for repeater stations (which can be solar powered, so you don't need a mains electricity supply) this should be feasible.

    Here are some URLs you might find interesting: HPWREN [ucsd.edu] (featured here recently) have a 45mb backbone using western multiplex tsunami [wmux.com] kit, and 802.11b [nocat.net] access points. They use solar power and batteries to power some backbone nodes.

    Some other people using mostly 802.11b kit who will have some information you can use: BAWUG [bawug.org] PersonalTelco.net [personaltelco.net] NoCat.net [nocat.net] Freenetworks.org [freenetworks.org]

    Using 802.11b or similar tech, you should expect each wireless hop to add about 5ms of latency, maybe a little more depending on distance. You can quite easily build a repeater by connecting two bridges together by a X-over cable. You could probably do this with Linksys WAP11 or similar, but over this type of distance you will find it much easier to use something like the high-spec version of Cisco Aironet 350 bridges [cisco.com] (the 100mW versions will push the signal a lot further - 25 miles with 24dBi antennas - you can use Cisco's own, alternatives include Superpass [superpass.com] (based in Waterloo), HyperLinkTech [hyperlinktech.com] and others.

    Aironet bridges let you set the distance of the link which modifies timing parameters (a slight problem with standard 802.11b over long distances), and their security is better than WEP.

    There's plenty of homebrew opportunities for antennas and other related kit, although I guess they're probably of more use to people who don't have a budget to play with (: There's a collection of links on this page [spacehopper.org] with a particular focus on homebrew kit.

  • Try this. Get 1 Watt amplifiers, 24dBi directional antennas, and 50' of LMR400 cabling from Hyperlink Technologies [hyperlinktech.com] as a kit. Get two kits. Then, get two Orinoco [orinocowireless.com] ROR-1000 bridges and Orinoco's 802.11b gold pc cards. You should be able to stretch that distance. We are using the same equipment, but with 15dBi wide angle and omni antennas for a ship to shore connection. We get about 10-15 mi. (we're using lower gain antennas than the 24dBi directionals.) You can check it out here [uconn.edu]. If you just need a point-to-point solution, using the Hyperlink 24dBi directional / amp kit and Orinoco ROR-1000s may be the way to go.
    • A plain 802.11 MAC will not allow a 45 mile distance. This has nothing to do with signal quality, but with round trip delay time. After sending a data frame, the MAC expects an ACK frame withing ~300 microseconds.

      Since the signal travels at light speed, every mile of round trip equals ~10.7 microseconds. After about 28 miles the round trip delay becomes higher than the ACK timeout value, and the 802.11 protocol stops working, no matter how much you have amplified the signal. This limit is the same for 802.11 and 802.11b, and will be even worse for 802.11a which has shorter ACK timeout values. Of course, if your product allows tuning of the ACK timeout value, you could theoretically stretch the limit.

      Another point to remember is that using 1W transmitters on standard 802.11 products probably violates your country's regulations.
  • by troutman ( 26963 ) on Sunday October 14, 2001 @08:24PM (#2428820) Homepage
    Check out Western Multiplex's line of T1-T3 point-to-point solutions [wmux.com]. You should be able to get 8 T1s over a 45 mile link. I know that their DS-3 (T3, 45Mbit full duplex) gear is around $18,000 per end, but it doesn't have the range that you need, because of the free space loss.

    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.

  • A lot will depend on where in our country you are. Industry Canada has their Schoolnet Initiative in the past, and I don't know what they have currently, but spend some time at strategis.ic.gc.ca and see what you can dig up. I'm also interested in decent bandwith to rual areas in Canada...where I want to live, I am about 5 kilometers from the closest Cable (ick, Rogers@home!) feed. I don't think that bell has ADSL out there yet. A company is starting to deploy wireless in a number of rual regions around Ottawa, probably using 820.11b, but I haven't investigated them much.

    Please make sure and follow up if you find a solution!

    ttyl
    Farrell
  • The BBC [bbc.co.uk] have a timely interview here [bbc.co.uk] with Bertrand Hartman of Omnired [omnired.com.ar], describing his rollout of internet access to a rural town in Argentina.

    Also theres this [bbc.co.uk] describing such done by the Peace Corps for Luki, Bulgaria.

    Finally, a former Ask /.:Internet Connectivity Options in Mozambique? [slashdot.org] may be of interest.

  • Do what MMNET [edzone.org], Middle Michigan Network. They got a bunch of the area school districts to band together to build a fiber network. It contains about 300 miles of fiber.

    The project worked so well, that they picked up the call to offer the region internet connectivity, through edzone [edzone.org].

    It is politically and financially difficult to do, of course. But, Publicly Owned Networks are a good thing... right?

  • Check into the Tsumami products from Western Multiplex, you will most likely find a solution that will work for you in your price range. http://www.wmux.com/products/index.html

  • Um, why wireless? (Score:3, Informative)

    by eric2hill ( 33085 ) <{eric} {at} {ijack.net}> on Sunday October 14, 2001 @11:36PM (#2429297) Homepage
    Can't you get a fractional point-to-point T1 from the phone company? They have to bring lines in somehow...

    45 miles is nothing when you expect to pay about $1000 per month for a full T1 over 250 miles. I'd guess you can get a fractional T or link to a frame cloud for about $500 per month and about $2000 per point. If your budget is $80,000, that leaves you with $70,000 (in one year) to pay for Internet services from an ISP. You should be able to get internet services for less than $1000 per month. If you're looking at $80,000-$4,000 (for hardware) = $76,000 / $1,500 (per month), you'll be able to have that active for over 50 months (that's over 4 years for those counting).

    Skip the huge outlay of money for a technology that will be sketchy at best in bad weather and go for something that works and is proven many, many times over. If you want equipment recommendations, let me know. You can pick up some standard T1 routers (Cisco) with an integrated CSU/DSU off eBay for close to $1000 each. Your ISP may not even require you buy one at their end if they've got space on their T3...

    All money estimated in U.S. currency.

    Eric
  • Why Wireless? (Score:2, Informative)

    by dorzak ( 142233 )
    I work with PTP circuits everyday all day long. I know of one guy who is paying well within their budget for a much longer loop.

    Currently in the US Worldcomm is waiving setup, they may do so in Canada as well, but I just priced an approx 120 mile T1, and the loop fees were only $670/month with 1 year contract. (Downtown Sac to North Shore Tahoe). The link up at the other end with a major ISP was $500/month.

    With a $120,000 budget, even Canadian this should be doable.
  • by isdnip ( 49656 ) on Monday October 15, 2001 @12:26AM (#2429449)
    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.
  • www.pcs.k12.va.us (Score:2, Informative)

    by russg ( 64596 )
    I helped setup the wireless system for this school a couple years ago. We used BreezeCom and Tsunami equipment. They have done much more since then. At 45 miles though you will have deal with the curvature of the earth. All wireless/microwave systems require line of site.
    We setup relay stations for the sites we couldn't reach by one line of site path. The director of IT at the above mentioned school has a great deal of knowledge in this area. I'm sure he would not mind sharing that information. Good Luck!
  • by N3GQF ( 213724 )
    Ok, I didn't read all the replies... So, I apologize in advance if this is a repeat. This solotion uses a combination of HAM and Commercial pieces. The commercial part of it is you'll need to license frequencies from the government. The HAM part of it is packet radio. There is a college in Italy that is using this. They have connection speeds ranging from 2Mb to 34Mb. Check out their web site here [unibo.it]. The theoretical limit is 155Mb according to the site. If your interested in reading more about packet radio you can check out The Tucson Amateur Packet Radio [tapr.org] Club. I'm not sure what is entailed in licensing frequencies from the government. But, it can't be that much trouble.
  • This [bawug.org] just appeared on the BAWUG list, with some info on Canadian regulations for the 2.4GHz band.

Prof: So the American government went to IBM to come up with a data encryption standard and they came up with ... Student: EBCDIC!"

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