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Ask Slashdot: Updating a Difficult Campground Wi-Fi Design? 237

MahlonS writes "I am a retired network hack wintering in my RV in a campground in southern GA. 3 years ago I reconfigured the Wi-Fi system to a marginal working ability; It's now ready for a serious upgrade, prompted by a new cable net connection replacing a weak DSL. 5 dual-radio HP Curve access points connect to a 6th via single or double radio hops (effectively a Wireless Distribution System) in heavily wooded space. Unidirectional antennas at the APs (the APs are in water resistant enclosures) are placed on poles above the RVs, about 15 feet above ground. Primary hops are about 300 feet to 3 of the APs, secondary hops about the same. Signal measurements indicate that there is adequate RF between the access points. In 2008, average user count averaged about 30 users; newer devices (smart phones, etc) will likely increase that number (winter population total is about 80 RVs). While the old design worked OK when lightly loaded, I suspect that the single DSL line generated so many packet resends that the APs were flooded. This is a quasi-State Park, so money is always an issue, but there is enough squawk from the user community that a modest budget might be approved. The main AP connects to an old Cisco router. Burying wire is frowned upon, due to shallow utilities, and campfire rings that float around the campsites — sometimes melting TV cables. Since I'm not up on current Wi-Fi tech, are there solutions out there that would make this system work much better?"
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Ask Slashdot: Updating a Difficult Campground Wi-Fi Design?

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  • Openmesh (Score:4, Informative)

    by Anonymous Coward on Sunday November 20, 2011 @01:51PM (#38117432)

    I'd look into some of the fairly inexpensive openmesh routers...they're great for extending networks (or running jasager). []

  • Too high (Score:5, Informative)

    by BitZtream ( 692029 ) on Sunday November 20, 2011 @01:52PM (#38117442)

    Lower your transmitters a little. Signals propagate horizontally (perpendicular from the antenna), this is why you need to have an AP on each floor in a house to get good signal. Not because you're on different floors so much as the signals just aren't going in the right directions.

    I know you're trying to broadcast over the RVs, but going over them also means no signal is getting to them in this case.

    • Re:Too high (Score:4, Funny)

      by Anonymous Coward on Sunday November 20, 2011 @02:05PM (#38117516)
    • Re:Too high (Score:5, Interesting)

      by FooAtWFU ( 699187 ) on Sunday November 20, 2011 @02:07PM (#38117532) Homepage
      Take a look at your options there and learn how to read antenna spec sheets: compare, for example, this directional antenna [] with this traditional one []. The first one can go on a high mount somewhere and point down at all the clients in a cone (roughly) and will mostly ignore things behind it (okay if it's on the ceiling). The second one throws out most of the signal in a pancake perpendicular to its long axis. This is great, if you're in that plane, and if there aren't a lot of walls in that plane between you and it. (The first one is an indoor antenna, though; I just use it as an example.)

      Too many outdoor deployments are radiating out their best coverage over everyone's heads. (You can also tilt the antenna a bit, but then you're essentially just painting stripes of coverage on the ground, which isn't ideal either.)

    • by hawguy ( 1600213 )

      Lower your transmitters a little. Signals propagate horizontally (perpendicular from the antenna), this is why you need to have an AP on each floor in a house to get good signal. Not because you're on different floors so much as the signals just aren't going in the right directions.

      I know you're trying to broadcast over the RVs, but going over them also means no signal is getting to them in this case.

      He'd have to have seriously high gain antennas for 15 feet to be too high. I once set up a temporary Wifi network where the only accessible mounting locations were 45 feet off the ground (with 2 mounting locations about 50 feet apart), and people were going to be standing within a 150 foot radius of the Wifi nodes.

      We used standard 7.5dB Omni's and got great coverage throughout the space even when standing directly under one of the Wifi antennas and 50 feet from the other one. We thought we'd have to tilt t

    • Not just this, but without external antennas the aluminium shells are going to block a good bit.

    • Re:Too high (Score:5, Informative)

      by Lyttek ( 992980 ) on Sunday November 20, 2011 @11:49PM (#38120972)
      I'll have to disagree with you on this, having actually setup a wifi system at an RV park. It is different than setting up a wifi hotspot in a building. The park owner asked for my recommendations about installing wifi to cover the park, and I gave them. The cost figures that I presented were higher than what he wanted and asked if we could do it another, less expensive way. What he wanted to try was a couple of telephone poles with an omnidirectional antenna for the access point, directional antenna for the backhaul link. If you were within a certain range (not far) it worked ok, but more than one or two rows of RV units away, it was no good. Keep in mind that RV units are essentially big metal cans... not the most conducive to getting a wifi signal into from the outside. What I wanted to do, and we eventually ended up doing, was installing a 70' tower with directional antennas pointed at an angle down. By using the technical specs of the antenna, we could figure the angles to get a pretty fair amount of coverage over the park, with almost line-of-sight from the antenna to each RV. This last bit was the key. By having the antennas too low, they would HAVE to penetrate multiple tin cans to get to the farthest units... and that just doesn't work, even with a 1-watt transmitter. A second park pulled me in for some consulting on the same type of thing, and they had antennas located about 10-12 feet in the air... I can guarantee you that unless you want to install an access point at each campsite, go higher. Lower does NOT work in this type of situation. We did keep one of the omni-directional antennas, because it worked so well. While most antennas are either horizontally or vertically polarized, this one was constructed to basically take the signal in any polarization that reached it. This park has trees as well, but how it would compare to yours is hard to say. Trees will absorb the signal quite a bit. One of the things I used to get the owner to put up the cash for the tower and etc was a bunch of signal-strength charts generated by netstumbler.
  • Fiber (Score:2, Interesting)

    by lightknight ( 213164 )

    It sounds like you're broadcasting from one access point to another, instead of from a wired connection to each access point.

    Just run fiber to the access points. It's cheaper than you think, and forms a guaranteed, secure connection. Good for a mile, and it doesn't care about EM interference of any sort.

  • our setup (Score:5, Informative)

    by Anonymous Coward on Sunday November 20, 2011 @01:55PM (#38117462)

    we've got 5 outdoor ruckus ap's spread across our park. (fairly cheap too)

    they'll mesh with indoor wifi ap's if you don't want to run ethernet to each one individually.

    the "smart antenna" design is actually pretty good. it supports dynamic beamforming, multiple signal paths etc. basically it just takes the path of least resistance, which helps a lot when dealing with a lot of walls/trees etc.

    you can give them a call w/ any questions you might have.

  • Layers (Score:4, Informative)

    by swalve ( 1980968 ) on Sunday November 20, 2011 @02:01PM (#38117486)
    I would run two networks, a backbone at say channel 6, and alternate APs at 1 and 11. Get highly directional antennas for the backbone, and either corner-directional antennas or omnidirectional antennas for the access points. Run the backbones up high, and the APs 12 feet or so.

    Try to eliminate any double hops via short cable runs and/or smarter backbone placement.
    • Re: (Score:2, Informative)

      by Anonymous Coward

      I agree with the separate networks, i would go further and use different freq band to go to the netework.

      If you can get get line of sight to the aps you could use a 5.8 signal to go from point a to b. ubiquity seems to have some cheap direction radio+antenna combinations.

  • From what I got your primary AP (1) connects to 3 secondaries (abc) and 2 more connect those (23). They are dual band are you repeating only over the 5ghz segment on a different ssid? Routing rather than bridging as people tend to just directly connect to these so limiting your broadcast domain is a must. 3 wires out to a b and c should do wonders, you might want to try power line networking for those wired connections since you will reuse your existing AC wiring, keep the 5ghz as a backup.

    • by Aczlan ( 636310 )

      you might want to try power line networking for those wired connections since you will reuse your existing AC wiring, keep the 5ghz as a backup.

      If power to the wireless access points all ends up at the same breakerbox, powerline networking would be the way to go in my book. Aaron Z

  • Marketing / Security (Score:5, Interesting)

    by vlm ( 69642 ) on Sunday November 20, 2011 @02:15PM (#38117576)

    This is a quasi-State Park, so money is always an issue, but there is enough squawk from the user community that a modest budget might be approved.

    because they can pull money from the marketing budget first as a lure to get people to come as a checkbox feature, secondly because you can install $100 wifi webcams at the "cool places" (pool, lakeshore, whatever) so visitors from the UK feel comfortably spied upon and the promotional web page can have "click here to see the scenic lakeshore live!" buttons.

    also they can pull a little money from the security budget, because the webcams can monitor boring yet important locations like the bar's cash register, the general store cash register, the service entrance, the equipment shed (the $20K nuclear propelled lawnmower, tanks of gas for the mower, etc)

  • Engenius APs (Score:3, Informative)

    by Mr. Lwanga ( 872401 ) on Sunday November 20, 2011 @02:17PM (#38117582) Journal
    Take a look at Engenius' access points, I think their multihop repeater solution might fit your needs []
  • by FooAtWFU ( 699187 ) on Sunday November 20, 2011 @02:18PM (#38117598) Homepage
    You think your APs are falling over due to packet volume? Are you just hooking up cheap Linksys stuff to these antennas or what? There's a reason that real enterprise-grade stuff costs more: you can throw 30 users at an access point and it doesn't crawl over into a corner and die. I favor Aruba gear, since I used to work there; Cisco stuff is also decent (but even more expensive). But they're not dirt cheap.

    On the other hand, if you think the DSL router's doing crazy stuff, maybe you should focus on making it not do that crazy stuff.

  • uBiquity (Score:4, Informative)

    by smpoole7 ( 1467717 ) on Sunday November 20, 2011 @02:24PM (#38117648) Homepage

    I don't think one vendor will supply everything that you need, but you definitely need to take a look at uBiquity. We've used their NanoBridges in studio-to-transmitter links several times and have been pleasantly surprised. The stuff is ridiculously cheap -- so cheap that we honestly wondered what could be wrong with it until we tried it. (Less than $160 for a pair of NanoBridges!)

    Ubiquity's Website []

  • by Above ( 100351 ) on Sunday November 20, 2011 @02:33PM (#38117694)

    Ubiquiti [] has some very cool products and customer support, you might want to look into their gear.

    If you can get line of site from the remote sites back to the central site you should use 5Ghz for the backhaul, and 2.4Ghz for the client side radio. This will reduce your interference. Also, the backhaul should use _very_ directional antennas since the two endpoints are known. This will also prevent interference. It doesn't sound like any of your distances are enough to require a multi-wireless hop, although your sight lines may require it. Avoiding a double hop will increase performance.

    You'll also want some intelligent QoS on both the WiFi and cable modem side. You don't want one user to be able to make the experience really bad for all the other users. For instance, if you had a 20Mbps cable modem you might want to limit any one IP/MAC to 5Mbps, or so. WRED or similar can also be your friend. Make sure there is a good local DNS server, as well

    • by pla ( 258480 )
      If you can get line of site from the remote sites back to the central site you should use 5Ghz for the backhaul.

      At the risk of posting essentially a dupe - Not in dense tree coverage, he doesn't.

      5GHz works great in opens spaces, but degrades horribly without line of sight. In this case, lower frequency will work much, much better.

      I'll second Ubiquiti (no, I don't work for them, but they have good cheap gear), but go with their 900MHz gear for the backhaul.
  • Test, and isolate. (Score:5, Insightful)

    by Vellmont ( 569020 ) on Sunday November 20, 2011 @02:39PM (#38117736) Homepage

    It sounds like you don't exactly know where your problems are, so how can you solve them?

    My advice would be to do some serious analysis of what's going on in your network. Hook up an ethernet sniffer to your internet connection and see what's going wrong. You suspect it's a lot of retransmissions do to the DSL, well find out if that's true. Consider buying a cheap spectrum analyzer (wi-spy can be had for under $100). Track when you get problems, and where. Throwing money and equipment at the problem is more likely to waste money and equipment than solve the problem. Since you're retired, it sounds like you're more short on money and equipment than you are on time to analyse and diagnose the problem.

    Once you actually know what the problem is, then you can go out to the wireless community and ask for a solution. K You're seeing a lot of very, very different solutions here because people are guessing what the underlying problem is, largely based on what's worked for them. Obviously you can't follow all of them, but which one should you try? Knowledge is power, and ignorance is folly.

  • Ignore the haters. They don't understand that camping in an RV park is not the "camping" they are thinking of. It's more like a portable cabin, and it's a great way to get out for an inexpensive and hassle-free vacation especially when you have little ones. And you still have the option of remote camping with the same rig if you really want to disconnect. Or using it as a base camp to take tent camping excursions.

    Sounds like what you really need here is to separate your "backhaul" form the APs. Sinc
  • 900MHz FTW. (Score:5, Interesting)

    by pla ( 258480 ) on Sunday November 20, 2011 @02:41PM (#38117760) Journal
    With line of sight problems and lots of water-containing organic obstacles (aka "trees"), lower frequency means much much better signal quality. Use a 900MHz WDS and many of your problems will vanish. I know Ubiquiti offers 900MHz kit, can't say for HP.
  • Then do it right. (Score:5, Insightful)

    by Lumpy ( 12016 ) on Sunday November 20, 2011 @02:42PM (#38117766) Homepage

    Stop being lazy and run freaking wire between the locations. you already have power there so you can run wire. you can use phone wire which is cheap and use ADSL modems for the links, again cheap.

    Honestly there is no magical wireless setup that will handle the load, you have to run wire if you want to avoid performance issues.

  • You might try outdoor grade signal boosters. I've had some decent luck with them. There's no substitute for power. That might reduce the number of hops, improving latency and cutting down on retries.

    • improving latency and cutting down on retries

      I first read that as "cutting down on retirees". Chainsaw campsite fantasy, back down in your hole!

  • One for distrobution of service, the other for devices connecting.

    I.E. each "point" will have 2 AP's, one which consumers directly connect to, the other which just communicates with other AP's on the site....

  • Quasi State Park? (Score:4, Interesting)

    by Doc Ruby ( 173196 ) on Sunday November 20, 2011 @03:24PM (#38118026) Homepage Journal

    What's a "quasi-State Park"? Obligatory "Georgia is a quasi-state" joke.

    What is that area really? Does Georgia allow people to live on public lands, even allow/provide utilities (however shallowly buried the wires) including cable TV and now wireless Internet? Do they make you move somewhere else to summer, after you winter in S Georgia? How often do you have to move? Do they charge you anything, like property taxes? Do you receive US Mail to your local address?

    The setup sounds wonderful. Or maybe we're talking about the (maybe not so) ex Communist country Georgia.

    Snark aside, my questions are serious. And it does sound wonderful.

  • OK, so Slashdot is answering your WiFi questions. How about telling us whether you get a better home out of a mobile home (integrated motor and driving seats, etc) or out of a trailer that you rent a car to haul the few times a year you actually move.

    • by mlts ( 1038732 ) *

      All depends on you. A class "A" rig with a "toad" (towed behind car) is good for a lot of people who fulltime because hooking and unhooking is easier. However, a 1 ton pickup with a fifth wheel is also a nice solution, especially if the RV will be parked for longer periods of time (fewer things to maintain on a trailer than a motorcoach).

      If you like getting away from it all, a truck camper (some truck campers like the Chalet ones have multiple slideouts, and can give more usable inside space than travel t

  • by GSloop ( 165220 ) <networkguru@sloop. n e t> on Sunday November 20, 2011 @03:47PM (#38118234) Homepage

    Look at ubiquiti's stuff. M5 Wireless bridges out to to the AP's and UniFi [normal or long-range] for the clients.
    Nanostation M5 [5Ghz]: []
    UniFi: []

    Not as slick as Ruckus or some other stuff, but incredibly cheap. [Bridges are about $200 for a pair - and super solid, massive through-put. UniFi is about $70 per AP.]

    You also get the ability to help pay for the system via UniFi. [Paypal subs, no admin reqd. Vouchers for "free" use etc.] That's all included for "free" in their system.
    Plus you can use Pico's for outdoor use. Already weather-proof.

    [I've not run the Pico's - so check it out in the forum: [] - you should be able to get your answers there.]

    It's really some of the best bang-for-the-buck for non super-high-density WiFi use around, IMO>


  • Do Like The WISP Do (Score:2, Interesting)

    by Anonymous Coward

    I work with a local WISP and they use Mikrotik products running on all three bands (900MHz, 2.4GHz and 5.8GHz) and they provide networks for many campgrounds and parks along with coverage for over 11 counties. Using 5 radios with omni antennas and doing a WDS mesh or relay you could blanket the whole park for less than you think. Ubiquiti radios are okay but they don't offer the management and configuration options like Mikrotik products.

  • Wireless and woods don't mix. Obviously, the only technological and economically viable solution is to cut down the trees, sell the lumber, and use a single AP with a nice powerful omnidirectional antenna.

    But seriously, its quite astounding that no one seems to be working on this very real problem, wireless and woods (or wireless with obstructions). I guess the neato factor of wireless, that it works at all, is blinding everyone to the fact that it doesn't work when something is in the way. Someone really

Things are not as simple as they seems at first. - Edward Thorp