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Wireless Networking Hardware

The Wireless Networking Question Roundup... 202

Posted by Cliff from the article-conservation-mode dept.
In the interest in preserving your clicking finger, we've rounded up several related Ask Slashdot questions into one, for your browsing pleasure. Today's installment features a return to wireless apartment complexes, enclosures for outdoor wireless equipment, and the search for the Best Wireless PDA.

Which 802.11b-enabled PDA?

Kent Brewster asks: "I've retired my Palm 7 due to sudden lack of all-you-can-eat service and lots of free WiFi in the area. Right now, I'm looking at HP's iPAQ h5455, Toshiba's e750, Palm's Tungsten C, and Sharp's as-yet-to-ship Zaurus 5600. What I'm after is the best possible mobile Web experience first and PDA functions second. Opinions, please?"

802.11b Issues for Apartment Complexes? (Revisited)

johaninroseville asks: "I am in the planning stages to build a wireless network to provide an apartment complex with last mile Internet access. There are about six hundred units, but only one to two hundred interested people. For those curious as to the general layout of the apartments, here is an overhead picture.

My experience with radio frequencies, antennas, and especially how well radio waves can penetrate walls etc is rather limited. My game plan is to get a feed into the POP / MDF, and have a rather strong omni antenna mounted on the roof of that building. The coverage of that omni antenna will provide the links to the seven APs that will probably be needed, mounted on the rooftops around the complex. The seven IDFs, (or APs or what ever you want to call them) will each have a Point-to Point connection to the big omni antenna. Hardware used for the seven IDFs is planned to be: directional antenna (for link to omni in POP) connected to bridge, bridge connected to AP, AP connected to a sectored panel antenna that will provide end-user access (to their PCMCIA/PCI/CF/USB Cards, or to their access point).

My biggest questions are what antennas to use? What strength? How well can the radio waves from an omni antenna and/or a sector antenna penetrate multiple walls, if at all? How far can one of these antennas cover, and then penetrate walls?

I would appreciate any help at all in this matter. Maybe somebody has done something similar, or have some useful links."

Ask Slashdot last covered wireless apartment complexes about a year ago, and it would be interesting to note if any of the new technologies, introduced in the interim, will make this job any easier.

Outdoor Enclosures for 802.11b Equipment?

And finally, this question from ETEQ: "I need to operate a small amount of networking and wireless equipment (Router, Cable Modem, and 802.11 access point) in an outdoor setting, but the problem is that I live in Minnesota, where temperatures can drop far below freezing and stay that way for weeks (not to mention frequent heavy snow)... Are there any outdoor enclosures that can be purchased on a Home or SOHO budget?"
This discussion has been archived. No new comments can be posted.

The Wireless Networking Question Roundup... More

The Wireless Networking Question Roundup...

Comments Filter:

  • outdoor use (Score:3, Informative)

    by McAddress ( 673660 ) on Monday May 19, 2003 @03:28PM (#5993856)
    make a waveguide antenna with a coffee can. it should last ok, and if it rusts, it is easy to replace.
    • Wave guide antenna would be fine for directional use but the user didnt specify if he wanted directional or omni. But you are in the right direction (haha pun). You might also want to look into the converted satillite dish antennas also. Because they are already ready already for the outdoor enviroments and could be mounted ontop of any structure, fence, ect.
    • Use pringle cans. They don't rust as easily. Of course the cardboard will fall apart even quicker, but that is beside the point.

  • outdoor enclosures (Score:5, Funny)

    by anonymous loser ( 58627 ) on Monday May 19, 2003 @03:30PM (#5993872)
    Are there any outdoor enclosures that can be purchased on a Home or SOHO budget?

    Am I the only one picturing a lawn gnome with a wire coming out of his butt?

  • Outdoor Enclosures for 802.11b Equipment?

    Well, since it is Minnesota I suggest an Iron Oxide and Aluminum [wisc.edu] enclosure. But this still may not be warm enough for winter time in MN.

  • For apartments... (Score:5, Informative)

    by Gortbusters.org ( 637314 ) on Monday May 19, 2003 @03:31PM (#5993880) Homepage Journal
    Many apartments have pretty thick ceilings and floors so the signal shouldn't get too far vertically, though the neighbor on the other side of the wall might want to bum some free internet and pr0n downloads on your expense. Solution: secure that network.

    • Re:For apartments... (Score:4, Funny)

      by dboyles ( 65512 ) on Monday May 19, 2003 @03:48PM (#5994001) Homepage
      Many apartments have pretty thick ceilings and floors

      Obviously we don't have the same landlord.
      • Sure, a 2-story or 3-story apartment building in Earthquake Country is going to be built out of wood-frame. That doesn't mean it isn't insulated well; you can do just fine with proper spacing, good sheetrock, and insulation if you want to. Shoddy construction is usually an artifact of housing booms, when lots of people are moving into an area and the contest is to get as many units built quickly as you can. (Ok, yes, that's most of Silicon Valley :-) I've lived in apartments in New Jersey that were jus
    • As an FYI, wireless signals don't travel very well vertically without the right antenna setup. If you just setup your antenna normally then think about it like tossing a pebble into a pond, the waves will travel outward a long ways, but only go up and down a little bit.

    • Re:For apartments... (Score:3, Interesting)

      by kent_eh ( 543303 )
      Instead of blasting each building with one big antenna (at a relatively high power) have you thought about running leaky co-ax (AKA radiating cable) in the hallway celings? Depending on the amount of re-bar in the floors, you could probably get away with every 2nd or 3rd floor.

      one manufacturer's product [reliancecables.com]

      another [lgcable4u.com]

      and another (PDF) [timesmicrowave.com]

  • apartment complex :-/ (Score:5, Informative)

    by UnderAttack ( 311872 ) on Monday May 19, 2003 @03:32PM (#5993883) Homepage
    couple things to consider:

    the main problem in my experience is wall penetration. Don't count on more than 3 walls (and this is stretching it if they are concrete). Consider mounting the antenna outside a bit away from the building, essentially hitting the outside wall. This will give you only one wall for all apartments.

    Don't forget about accountability and security. Even if billing is not an issue, you don't want someone in your building to go wild and start a hacking crew. Static IPs are a bit accountability help, NAT is though

    • Re:apartment complex :-/ (Score:5, Funny)

      by Anonymous Coward on Monday May 19, 2003 @03:38PM (#5993926)
      the main problem in my experience is wall penetration

      Find a 240V outlet and use lots of vaseline.
    • the main problem in my experience is wall penetration. Don't count on more than 3 walls (and this is stretching it if they are concrete).
      So we finally see that all those penis enlargers and herbal viagras really DO work.
    • Forget about putting it on the roof. Getting a signal through multiple floors and ceilings will be tough. Fortunately every apartment should have a few rooms with a window. Mount it outside and tell everybody to put their antennas near the window that faces your AP. You don't have to get a wireless signal to every single point in the building, just to every apartment unit. The best place would be an interior courtyard.

    • Backhaul vs Client access (Score:5, Informative)

      by Myself ( 57572 ) on Monday May 19, 2003 @07:39PM (#5995433) Journal
      To solve the channel problem, consider this:

      Use a single 802.11a AP on the roof above the MDF with a decent omni on it. Then, at your other locations around the complex, use more .11a gear with directional panels pointed back at the master. Set them to bridge the wireless side to their ethernet jacks. Now you've essentially got "wire" to all your locations, without stepping on the 2.4GHz spectrum.

      Then at each location, connect one or more 802.11b/g APs to the ethernet. I say "or more", because you may wish to use several APs with narrow sector antennae, to provide stronger signal to a broad area.

      Another poster pointed out, you'll have to make people swear not to use 2.4GHz cordless phones. Since 802.11b isn't really spread spectrum, [ivy.net] it doesn't handle interference well.

      People in their apartments will need to realize, they're not aiming for the AP on their own building, they're aiming for the building across the way. Explain that 2.4GHz is line-of-sight, so if they can't visually see the AP, they might have problems. Consider marking the rooftop locations with flags.
    • It really all depends on the power output of the AP and people's cards. For example, I have a 17dBm AP and a 15dBm wireless card. At home I can get it to go through about 3 walls (35 feet) and still have say 25% strength. At school our walls are made out of block and have had years of paint (probably led) and I CAN'T GET MY AP TO GO THROUGH MORE THAN ONE WALL. That's right one and only one. After going through a single wall the signal is at 5-10% strength. I imagine floors and stucco walls at the Apt.

  • The best wireless solution... (Score:3, Funny)

    by cruppel ( 603595 ) on Monday May 19, 2003 @03:33PM (#5993887) Homepage
    for any problem can be made with a few household items:

    1. A tin can
    2. Another tin can

    Since it is a wireless system no string or twine is neccessary. You'll find that with a little imagination The Tin Can System is effective at several kilometers.

  • wireless pdas (Score:3, Informative)

    by ptorrone ( 638660 ) * <pt.adafruit@com> on Monday May 19, 2003 @03:34PM (#5993901)
    for wireless pdas, the ipaq 5455 is really the way to go. wifi, bluetooth and finger print recognition. add to that, the ipaqs have tons of accessories, so you can even use a gsm card and use the ipaq a cell phone (and gprs / gsm data services). also, the ipaq along with a t68 or nokia 3650 is a pretty good combo too.

    cheers,
    pt
    • Sure the ipaq is great -- if you have an extra $700 laying around. Last I checked, the Dell Axim was less than $300. Add a compactflash wireless card for $70 and you've got a PDA with more memory and better options for expandability (IMHO) than the IPAQ -- at about half the price.

      • Re:wireless pdas (Score:2, Informative)

        by ptorrone ( 638660 ) *
        that's true, but if you want bluetooth and wifi you'll need to swap cards out all the time. here's a fun ipaq 5455 trick...after setting the registry key \HKLM\SOFTWARE\Widcomm\BtConfig\Services\0005\Enab led from 0 to 1 you can pair the just about any bluetooth heaset to the ipaq and use that to listen to music.
    • Another option is that if you have a cell phone that doesn't have Bluetooth but supports a serial connection, there are a lot of serial adapters available that you can use your phone as a modem (in a sense) and connect to GPRS that way. Worse case, if the phone has an IRDA port, you can connect it via IRDA and get okay speeds (I have a GSM phone but elected not to get GPRS due to cost, and I use IRDA with my Jornada and get enough speed to view a couple of pages, but not fast enough to do a remote sync with

    • Don't get an ipaq... (Score:5, Informative)

      by lpret ( 570480 ) <[moc.liamtoh] [ta] [24terpl]> on Monday May 19, 2003 @03:50PM (#5994019) Homepage Journal
      I had the "pleasure" of using the 5455 and I found it to be completely useless. Unless you are somehow attached to the ipaq style or whatever (and you come from Palm) I would not suggest this as the Wifi Pocket PC of choice.

      I would suggest the Tungsten C. I borrowed it from a friend for a day and was utterly impressed. The Palm OS 5 is very peppy with the new processor and the battery life is simply amazing. Most Pocket PC devices can only last about 7-10 hours, and only 2-3 with wifi on. However, the C can last up to a week, or a good 11 hours with Wifi. Not only that, but it does a better job rendering. Considering you are coming from a Palm device, I would recommend this C because programs will also be compatible.

      • Re:Don't get an ipaq... (Score:5, Informative)

        by kalidasa ( 577403 ) on Monday May 19, 2003 @04:17PM (#5994197) Journal

        I've had a C for about 2 weeks. It's fantastic. Only issues I've had are synching to OS X via wireless (10.2.6 broke it; it worked fine before, and still synchs via cradle and synchs to Windows XP via WiFi), and some of the 3d party apps seem to need to be updated for Palm OS5 (VNC seemed to work, and LFTP, but there were times I'd have TCP/IP troubles and I couldn't track down which app caused it). Also, Graffiti 2 is not fun for someone who knows Graffiti 1 well (yes, you can do Graffiti on the screen if your input settings are right).

        WiFi range is about 3/4 what my iBook gets. Set up was easy, and switching networks is easy. Cons: can't do Bluetooth (not sure why), can't do MP3 (but that's what the iPod is for), didn't come with the mic and earphone for voice mail, no Windows RDC client (which I guess means switching the Windows machines to VNC). Haven't had the opportunity to test the Kinoma video player. If you're coming from a Palm, the 65 MB and the 400 MHz processor will shock you. I didn't think I'd like the keyboard, but I'm using it 1/2 the time now.

        Of course, if you're planning on traveling around a lot and want to get Blackberry-like service, go with the W, not the C. The W is more cell-oriented. But if you want something to use in the office and at home, and at the occasional hot spot (if you want to pay T-Mobile or somebody the subscription fees), the C is a nice piece of work.

    • for wireless pdas, the ipaq 5455 is really the way to go.

      It's likely to take the best part of a year (going on past experience) for HP to get Linux working on this model [handhelds.org] as well as it does on the 3[68]00s. Also bear in mind that there will probably never be native support for SD cards, though MMC cards do instead.

      You really, really want to avoid being stuck with PocketPC for any length of time, trust me.
    • let us not forget the sony Clie nx70 line. Wireless slot and a keyboard some with digital cameras. I have one of the older Clies that does not support 802.11b but have loved it the screens look good in low light or day light...

  • Outdoor enclosure? (Score:3, Interesting)

    by JUSTONEMORELATTE ( 584508 ) on Monday May 19, 2003 @03:35PM (#5993910) Homepage
    If the fine folks at Tupperware/Rubbermaid can't help, how about Coleman or Igloo coolers?

    --
    • With the tupperware option, do you have to go out in the spring and burp your installations then?
    • Mods, let me save you the trouble of reading this comment -- it's -1 Offtopic. Have fun

      I'm baffled at the parent's moderation. I wasn't aiming to be smart-assed about the question of outdoor enclosures, and I'm well aware of what high-budget projects can do, either with existing telco companies or with folks like Pelican.
      For those of us working on a shoestring budget, a silocone-sealed Igloo cooler makes a great enclosure, and costs less than US$20.
      But ok, so it's Overrated. Whatever
      How does:
      40% O

  • Pocket IE and Palm web browser (Score:5, Interesting)

    by questionlp ( 58365 ) on Monday May 19, 2003 @03:38PM (#5993929) Homepage
    A couple of weeks ago, I got a chance to dink around with the Tungsten C at CompUSA and browsed around to a couple of sites, including Slashdot, and the web browser seems to render pages a lot better than Pocket IE included with the Pocket PC OS. Pocket IE is closer to IE3/IE4 than current versions of IE (though IE in CE.NET, which isn't available for Pocket PC hardware, is closer).

    Either browsers do not support pop-up windows, which is both good (for pop-up and pop-under ads) and bad (if you are using a webmail system that depends on pop-up windows). Also, trying to read something on a 320x240 screen is a wee bit difficult. The Tungsten C's display (320x320) gives a little more real estate for rendering web pages, though the fonts used my take a little getting used to if you are used to Verdana, Times or Bitstream's Vera.

    Speed-wise, the Tungsten C seems a bit faster and more responsive when browsing the web than an iPaq with the same processor, memory and built-in WiFi. For me, the location of the navigation disc is a bit too low for me, but after using it for a couple of minutes, I got used to it.

    As far as a previous poster's question on why 802.11b instead of 802.11g? I think there are a couple of reasons right now: 802.11g eats up more power (thus run a bit warmer) and the chips used for it aren't as compact as 802.11b chips... that and I'm not sure how much I/O is provided between the processor and the bus that the WiFi controller would connect to (which could end up being a bottleneck). That and I think almost all of the 802.11g PC Cards available right now are CardBus only, which I don't think any PDA (clamshell or not) supports.
    • I've tried browsing through Pocket IE on a Dell Axim...and man does it suck. It is basically IE 3.02 or some ancient crap like that, modified and stripped down to work on a PDA.

      I can't wait for the day that Opera runs on a PocketPC.
      • funny you ask for opera, the Sharp Zaurus SL-5500 (and I'd assume 5600) runs linux, comes with Opera, and works with every WiFi CF card I've stuck into it. It really is a great little machine. Oh, and Opera renders hella fast on it, and give 5 levels of zoom too! Even slashdot's god-aweful design works well on it!

  • 1 omni - 7 APs... (Score:5, Informative)

    by dietlein ( 191439 ) <(dietlein) (at) (gmail.com)> on Monday May 19, 2003 @03:40PM (#5993941)
    ... it won't work. At least, it won't work very well.

    There are only 3 non-overlapping 802.11b channels, or 4 if you do it right. Either way though, that isn't 7.

    However, if you can get it down to 3 or 4 links, don't use omnis anyway - use some little 8dBi-14dBi patch antennas, and do highly directional links to the radios you're bridging to. You only want to use omnis for client (think people moving around, unknown target direction) access.

    The above is what the traditional thinkers would say. And what you were probably thinking, given the fact you said "point to point" link for the omni -> client links.

    You can get around that barrier, however, if you do a single AP at your POP, and the bridged radios are simply looking to the AP for client access. The downside to this is that all the bridged radios will be sharing the bandwidth of a single channel, but you can have 7 (or more) links from your central antenna this way.

    And if you're going to do it that way, get two 15dBi 180-degree sector antennas (cell-site quality), put them back-to-back, and do a combiner feed to your AP box.

    • It will work, it will just reduce throughput. Overlapping channels are a non-issue in bridge mode. Basically the bridges are acting as clients to main AP with the omni, there is no problem with multiple clients talking on one channel or 802.11 anything wouldn't work. Personally I would use 802.11a for the backfeed because you would get more bandwidth, less rain fade, and would not risk interference with the site AP's. In reality I doubt it matters all that much because their uplink will probably not be fast

    • Re:1 omni - 7 APs... (Score:2, Interesting)

      by Ugmo ( 36922 )
      I totally agree with the idea of using directional antennas.

      The first wireless set up I did, I figured put the antenna up high where everything can see it. Even though I was only using it as a way to connect a one building that was offnet to another that had a T1 coming into it. Trouble is I put it up too high and picked up other traffic that interfered on all the available channels at times. We called in an expert. He placed antennas that were just powerful enough to do the job in out of the way corners s

  • Apartment Complexes - 2.4 GHz Cordless Phones (Score:5, Informative)

    by Ssolstice ( 198935 ) on Monday May 19, 2003 @03:41PM (#5993955)
    You'd better let the residents know that they shouldn't be using 2.4 GHz cordless phones on the premises, or they'll be knocking out the wireless connections for computers in the area.
    • anyone ran into that issue? I have never...

      • It's definitly been an issue with the Netgear wireless router I installed in my dorm room (model MR814) and my 2.4 Ghz phone. While the router is idle, I get a constant soft clicking in the background, not too bad. If I'm on my laptop downloading or doing heavy browsing when someone calls, there's a good bit of static-like interference.

        My roomate and I both have the same model of phone (he has the same problem, BTW), so I'm not sure if some brands of phones interface better with some brands of access

    • What makes you think 2.4GHz phones will keep knocking WiLAN's off the air? Put one on a spectrum analyzer. They only use about 2MHz out of the ~80MHz available. 802.11b/g use about 22MHz.

      Anecdotally, I have 2 V-Tech 2.4GHz phones running off of the same base, and a 802.11b network in my apartment and don't ever have any issues, even during file transfers.

      Got data?
    • Actually I think the warning should be that their 2.4 ghz phones might actually stop working.

      The funniest thing I have ever seen was during a site survey, we pointed a 24dbi grid antenna with enough power going into it to probably cause the Friendly Candy Company to frown. There was a guy on a 2.4 phone that was walking beside us. He walked in front of us and about threw the phone to the ground. "Dammit I just bought that phone from Wal-Mart and now it is making that kind of noise!" I laughed so hard m

  • Useful link for supplies (Score:4, Informative)

    by TopShaman ( 136172 ) on Monday May 19, 2003 @03:42PM (#5993959) Homepage
    Here is a link to acompany that proved useful that last time I was installing wireless LAN's.
    http://www.hyperlinktech.com/index.html. They have a full assortment including heated outdoor enclosures and antennas and amplifiers and AP's and more!

    • Re:Useful link for supplies (Score:2, Informative)

      by Anonymous Coward
      I bought a 900Mhz, 14dBi yagi (HG914Y) from them for making cell phones work at my mom's no-cell-reception house. It works extremely well, and I love the welded aluminium construction and white powder-coating.

      The other place I considered getting the antenna was MaxRad (no points for guessing their website URL) but I saw one of their antennas, and it's just a steel pipe with holes drilled in the sides for the passive elements - ugly. Also thought about Wilson (wilsonelectronics.com) but the yagi portion of
  • ...to provide an apartment complex with last mile Internet access.

    That must be quite some apartment complex.
  • The subjects are: (1) PDA recommendation, (2) antennae for residential wireless and (3) "outside plant". I just don't see how these questions can be seen as "related" (other than 802.11 in the subject). Am I the only one?

  • Waterproof and affordable (Score:4, Informative)

    by ronmon ( 95471 ) on Monday May 19, 2003 @03:49PM (#5994009)

    I have built two splashproof computers for marine surveying on small boats. Pelican cases [pelican.com] are what I used. You only need to seal the one or two through-case holes that you will need to run your wires.

    I would post a link to some pics, but my home server can't handle the Slashdot effect.

  • I have a Zaurus and it works great for wireless. I can ssh into my home computer. Opera browser works well, and there is Kismit and nmap for some fun wardriving.

    On the downside, if what you want is something to keep track of your schedule and address book it is less than satisfactory, but if your want a wireless linux box that can fit in your hand Zaurus is what you want.

  • Just do it! (Wireless Apt. Complex) (Score:5, Interesting)

    by Jack William Bell ( 84469 ) on Monday May 19, 2003 @03:53PM (#5994037) Homepage Journal
    I am running an open node in my apartment with a broadband Net connection. A co-worker in the same building has wireless, but no Net connection and was hoping to use mine, but the signal was too weak. The other day he was checking the signal again and found yet another 802.11B AP that gave him a good signal and had a Net connection.

    My point is this: Just encourage as many people as you can to set up open AP's using off-the-shelf AP's and whatever Net connection they have. Don't tell the providers. Don't worry about setting up complex routing or other network stuff (except making sure the AP's are on different frequencies to avoid stepping on each other). Don't sweat the details. Don't worry about who pays for what. Just do it.

    The amazing thing about 802.11B is that it will probably work fine.

    • Re:Just do it! (Score:3, Insightful)

      by anticypher ( 48312 )
      This is what I do now. I have an open AP on a specially firewalled port, and it only allows web browsing through a proxy server. All other traffic is blocked, except for a few neighbors who know how to authenticate to my firewall and have less restricted access.

      My AP is in the top of the house, with a nice omni antenna [tux.org] on the roof covering my neighborhood. I coordinate with several neighbors so our channels don't overlap. One neighbor in a shielded area has put up a yagi pointed at my omni, and gets a 2Mbp
    • That's a great trick- I have this one where I put money into a newspaper stand, and then I take a pebble and jam the latch so it won't lock again. It's really swell, cause it lets whomever wants a newspaper have one for free, and it doesnt cost anyone anything!

  • outdoor inclosure (Score:3, Interesting)

    by bobsalt ( 575905 ) on Monday May 19, 2003 @03:53PM (#5994041)
    one of the WISPS here in Iowa throw the equipment into an old cooler, then water proof it with silicone. Not sure if straight Styrofoam or like a Coleman one. I just remember the guy saying it has survived -20 and +100 degrees on op an old grain silo.

  • Outdoor Enclosures for 802.11b Equipment? (Score:4, Funny)

    by FreeLinux ( 555387 ) on Monday May 19, 2003 @03:57PM (#5994069)
    For the low budget solution that you request, I'd say to build your own. Further, I feel that you should use a small "log cabin" design so that it is environmentally friendly, or at least asthetically pleasing. You could build your log cabin out of these [duraflame.com] inexpensive logs and if the weather gets too cold, just put a match to it.
  • My choice is PocketPC for several reasons. First up, lets not beat around the bush. Palm is currently playing catch up when it comes to having multimedia and Internet capabilities on their PDAs.

    Browsing has been and continues to be pretty lousy on Palm devices mostly due to the available browsers. Having 802.11 speeds is waisted when your browser can only render text and simple images. PocketPC's all come standard with PocketIE which is basically a light version of IE. It renders pages very accurately
    • A Sharp Zaurus SL-5500 for $199 and a $50 WiFi card gets you a heck of alot for little cash. It's comes with the Opera browser and all the normal PIM apps. If you want other apps, check out the thousands of apps on the Killefiz.de and Handango.com sites. Battery life might get you down if you like a bright frontlight. The SL-5600( new ) has 2x the battery and a 400MHz XScale(broken PXA-250) CPU for over 3 hours of continuous WiFi( ~6h via Bluetooth ) use.

      And what about those C-7xx devices with 640x480 scre

  • Weather-Proof Boxes (Score:4, Informative)

    by serial frame ( 236591 ) on Monday May 19, 2003 @03:58PM (#5994075)
    Here is a great node on SeattleWireless.net's wiki that details the construction of an outdoor wireless access point, using relatively cheap equipment found at a hardware and/or electrician's store.

    http://www.seattlewireless.net/index.cgi/WaterProo fBoxes [seattlewireless.net]

  • wireless AP to wireless AP? (Score:5, Insightful)

    by PapaZit ( 33585 ) on Monday May 19, 2003 @03:58PM (#5994076)
    An important question: Why set up wireless AP to wireless AP links for the apartment complex? That seems prone to failure.

    Most installations that I've seen use wires to the APs (often with Power-Over-Ethernet, to reduce wiring to a single cable). That way, you have fewer channel collisions, less overall wireless traffic, and significantly lower latency. You can put all of your wires in hallways, basements, and other "public" areas where you can work without going into people's apartments. Too ugly? Use drop ceilings and ceiling-mounted cable runs. Not to mention that it's far harder for a repirman to mess up a cheap 10/100 switch than an elaborate antenna array.

    Also, think hard about setting up some sort of monitoring system. You want to have someone on the way to fix a failing AP before the angry calls come in.

    • I'll second that. APs to APs as distribution is unworkable. There are only 3 channels you can use on 802.11b which don't overlap, and you can't have an AP retransmitting on those or nearby frequencies without dropping your transmission speed to modem levels (or worse).

      If you can't pull/hijack some wire pairs from the PoP to outlying buildings, then you will have to go to an 802.11a distribution backbone, with the APs routing/repeating the signals onto 802.11b. That means the APs will be even more expensive

  • A good wireless PDA (Score:5, Informative)

    by leeet ( 543121 ) on Monday May 19, 2003 @04:03PM (#5994105) Homepage
    I wouldn't consider it a PDA actually. The Zaurus 5500 is more like a real computer, just small and less powerful (less upgradable too). But nonetheless, it is very powerful and you can have pretty much anything that's compilable.

    I'm a linux freak (and admin) so this is a nice tool for me. I can ssh to work from my living room and fix stuff at home :) Or watch movies from my NFS server, etc. I don't use other features like agenda or address book so I can't say about those. On the wireless side though, it's excellent. I guess it also depends on the type of card you have. Just make sure you have one that's supported under either the "stock" Zaurus ROM or OpenZaurus (which is way better)

    Also, since it's Linux based, things like Kismet are ported and work real nice. The only drawback is the battery and I consider buying a less powerful 802.11b card as mine is not power-friendly. Other than that, I get good milage with a base at work and at home. I rarely use it for more than 1-2 hours. I can't wait for the Sharp "C" series to be available as it will have a bigger keyboard. Until then, I'm glad I ditched my Palm Vx, it was useless :)
  • As for browsing from a PDA, I've found Thunderhawk from Bitstream invaluable. I've found it to render pages in about the same time, sometimes even a little faster, although there are delays when scrolling up/down on a page. The big advantage is that it is able to scale a page, rendering it at the equivalent of up to 800x600 on a pocket pc PDA. I can view slashdot, as it looks on a PC, from my iPaq. There is a yearly fee of $50.00, but you can get a one month free trial if you're interested in it.

    http:/

  • Wireless PDA's: Sony Clamshells (Score:5, Informative)

    by mliu ( 85608 ) on Monday May 19, 2003 @04:07PM (#5994138) Homepage
    If you don't mind Sony and all the baggage that comes with them, their clamshell PDA's are outstanding wireless PDA's. They have a CF slot dedicated to just being used for 802.11b cards (though if you buy a 3rd party driver you can also use CF memory cards in it), and they have the best screen bar none on PDA's to date. 320x480 of web-browsing pleasure (well, relative to other PDA's anyways). That's twice the resolution of any PPC-based handheld.

    The ones you'd want to look at if you're interested are the NX60, NX70V (same as NX60 with a crappy camera), and the NZ90 (only if you're really into getting a gigantic PDA with an actually decent digital camera built-in).
  • I had a Zaurus 5500. I loved it, and the web experience was great (with your choice of Opera, that comes pre-installed, or Konqueror, which you can download and install) but mine broke, and when I sent it in to Sharp for repair they told me nothing was wrong with it and sent it back to me. I'm returning it for a refund.

    I'm still trying to decide what I want to replace it. The Yopy [yopy.com] looks great but as they don't take US credit cards, that means I'd get no additional protection on my purchase, and given tha
    • you sent it in for repair and they said it was fine? Didn't you tell them what was broken and how to reproduce it? Something sounds fishy here as I've had nothing but great success with my dealings with Sharp and their repair facilities.

      You might try again with a better problem description. IMHO.

      LoB
      • Don't patronize me. It had a nonfunctional button. Seems pretty straightforward to me. I have been using and programming computers for 28 years. I think I know how to describe "this button doesn't work" in plain language that a support engineer can understand. I have *been* a support engineer. I *manage* support engineers now.

        When I tried putting the unit back in service, in the vain hope that perhaps the problem was just caused by humidity, another button proved to be intermittantly nonfunctional. The pow
  • What are people doing with 802.11 and PDAs? I'd love to get a modern PDA + 802.11, but ideas about what to do with it escape me. Anybody have inspirations for me?

    Heh I bought a PocketPC the year they started coming out, and by far the most useful thing I've done with it is synch it up with AvantGo so I have something to read during my morning dump. (hey, it's still considered work!) PLEASE give me something better I can do with it!

    • Making a PDA wireless makes it infinitly more usable. You can receive your email on it, browse the web, connect to VNC servers (not for apps but for emergency maintenance), do VoIP with it, etc. And then there are things like data aquisition that are more vertical market but which can often be accomplished with a wireless PDA rather than an expensive purpose specific device.
    • Checking weather reports before living home each morning.

      Checking public transport reports.

      Writing emails while in the move and sending them with one click when I get home.

      epr0n in more comofrotable places than my computer's chair....
  • Think about other computing equipment that need to be in thease environments. The best people to speak to would be the people who manufacture traffic lights, CCTV systems and cable tv systems.
  • What you are looking for is a heated NEMA enclusure. Many places sell them for a variety of applications including wireless. Here [hyperlinktech.com] is one specifically designed for wireless and with the failover heaters it can operate down to -45C.
  • The Sprint Treo 300 is the best device that fits what you want. You want good unlimtied data - sprint is the only nationwide person that offers it cheaply ($10 a month), and it is about 3 times as fast as dialup. It runs Palm OS, works great as a PDA, surfs the web very nicely using Handspring Blazer web browser, and than last of all can act as a phone. Read a review and user comments about it here: http://www.treocentral.com/content/Products/facts h eet-89-50.htm
    (for sake of disclosure I am an editor of

  • The ultimate Wi-FI PDA? (Score:3, Interesting)

    by Wesley Felter ( 138342 ) <wesley@felter.org> on Monday May 19, 2003 @04:29PM (#5994302) Homepage
    The ultimate Wi-FI PDA appears to be the Samsung Nexio S160, with a big, high-resolution screen for Web browsing. It's not officially sold in the USA [dynamism.com], it runs WinCE, and it costs as much as a computer, though.
  • This is a little bit more professional (i.e. expensive) than most of the other suggestions, but the BARWN [barwn.org] folks use Stahlin cases in their outdoor routers [barwn.org].
  • What do you mean by "Sharp's yet-to-ship 5600"?

    Do you mean you've order one, but it hasn't arrived yet? Because it's certainly not difficult [sharpplace.com] to order one of those. (They say it's in stock).

    No need to go through a speciality importer [dynamism.com] such as for the more exotic Zauruses.

  • 802 interference (Score:2, Interesting)

    by anjrober ( 150253 )
    I saw a few posts about cordless phone interference and 802.11 and wanted to add a recent experience. I recently added the MP3 capapbility to my Tivo and was streaming MP3s off my shared drive (linux of course) via 802.11b. Works great. (The Tivo MP3 play functionality sucks but thats a different story). So i'm listening to the music just fine and my wife puts dinner in the microwave. Now we have all heard about microwaves interfering with 802 before but i have never had a problem before. So as soon a
  • Ok, so now you are probably more confused than when you started. People are bombarding you with stuff like "use different channels", "why not cable each AP" etc. Your basic idea is to avoid ethernet cables to the APs and personally I think this is a good idea, as you may find you have to stick extra APs in all sorts of out-of-the-way places to cover black spots. I'll continue this post on the assumption that you are going to stick with this plan and use radio to feed the APs rather than cable.

    (note: your b

  • 2.4 GHz radio wave propagation (Score:4, Informative)

    by mobileone ( 615808 ) on Monday May 19, 2003 @07:00PM (#5995216)
    Back in the early nineties I spent some months doing indoor radio propagation measurements in the 2 GHz band. Basicly there are a few rules to observe when designing a wireless link:

    1: In free space the signal strength is inversively proportional to the square of the distance. Double the distance and the signal drops by 6 dB. Increase the distance by 10 times and the signal drops by 20 dB.

    2: Walls, buildings and trees attenuate the signal. As a rule of thumb a concrete wall attenuates the signal by 20 dB. Transmitting around a corner attenuates the signal by 10 dB. Wooden doors and windows will let the signal pass through with a typical attenuation of 10 dB.

    3: Big flat surfaces reflect the signal. This means that you might be able to connect to a friend in the same appartment block by "reflecting" off the building on the other side of the road, even if the direct line between you is obstructed by several concrete walls.

    Let us assume that the coverage of your wireless link in free space is 500 meters when using omnidirectional antennas. If you increase the antenna gain by 20 dB the coverage will increase to 5 km. If on the other hand you have to pass through a concrete wall then the original 500 meters will be decreased to 50 m. Add another concrete wall and we are down to 5 meters!

    As I understand your apartment complex project the users should be able to use their WLAN cards in all rooms of the flats. To be on the safe side you need line-of-sight between the access point and the facade of each flat. This of cause would require quite a lot of access points.

    Alternatively you might be able to use a few access points located at high points even if there is not line of sight to each flat. The signal would then be scattered and reflected of the neighboring buildings. This however would attenuate the signals, and your poor users might have to stand by the windows to get a good connection.
  • With the number of people getting wireless devices for their homes riseing and the people still forgeting to secure their routers and access points to prevent unsigned people from using their connections, an amazing new concept up as popup in my appartment complex. Their is a shared access setup going on. Everyone here has a different type of connection (Cable, T1, DSL, Satelight, and even DialUp) but most of us use a wireless router so we don't have to run 10base-T around our appartments. After booting up
  • Have a look at http://www.intersil.com/design/prism/papers/sympo s um.pdf [intersil.com] to see a summary of the loss you'll get through various materials. (page 4). Two other materials I've heard about but aren't listed are plaster with metal lath, and rebar concrete. Both will drop the signal dramatically. They basically both as as a faraday shield. Rebar concrete is what's used in most apartment buildings, it's concrete embedded with steel bars. Plaster in walls of houses often has a metal mesh called lath in it. In bo
  • I just returned my Tungsten C the other day, and I'm falling back to my Palm III.

    Now don't take this as a negative on the Tungsten C. The primary reason for my returning it is due to restrictions at my job; they weren't going to let me hook it up legally, so I figured I wanted my $500 back. However, here is some notes on using it for two weeks. Note that this comes from randomly playing with "modern" Palm devices over the last few years, and also the perspective of upgrading from an old Palm III.

    INITIAL

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