Become a fan of Slashdot on Facebook

 


Forgot your password?
Close
typodupeerror
×

Wi-Fi Routers - The Differences for Each Region? 46

Posted by Cliff from the variable-configuration-trees dept.
Wi-Fi Wonderer asks: "I've been wondering what the difference is between the different regions that can be set on a Wi-Fi router? I know the region determines which channels are available, but I can't find any concrete information on anything else. Do regional settings also determine power output, bandwidth, and/or encryption mechanisms? If you are in a Wi-Fi dense area does it make sense (legal ramifications aside) to choose a different regional setting so as to avoid interference? Will one region give a greater broadcast range than another? Is there any documented information on exactly what configuration settings go with each region?"
This discussion has been archived. No new comments can be posted.

Wi-Fi Routers - The Differences for Each Region? More

Wi-Fi Routers - The Differences for Each Region?

Comments Filter:

  • It's hardly a secret (Score:5, Informative)

    by Anonymous Coward on Wednesday May 03, 2006 @09:17PM (#15259064)
    United States uses channels 1-11, Europe uses 1-13, and Japan uses 14. Changing it won't get you anything, as most people use 1, 6, and 11, and 13 isn't far enough from 11 to save you from other user inteference.

    Google is your friend.

    • you spoiled it (Score:3, Funny)

      by Anonymous Coward
      now what will we spend hundreds of posts rambling about?

    • Re:It's hardly a secret (Score:1, Informative)

      by Anonymous Coward
      Actually, Japan now allows use of 1-14 now. The only restriction on 14 is that 802.11g is not permitted (but 802.11b is).

      --sf

    • Re:It's hardly a secret (Score:3, Informative)

      by biglig2 ( 89374 )
      Too lazy to google? Wikipedia is your friend too: http://en.wikipedia.org/wiki/Wifi [wikipedia.org]
    • United States uses channels 1-11, Europe uses 1-13, and Japan uses 14. Changing it won't get you anything, as most people use 1, 6, and 11, and 13 isn't far enough from 11 to save you from other user inteference. Google is your friend.

      Yup. That pretty much says it all. Sorry for the redundancy, and all. Does this kill the thread?
    • Changing it won't get you anything, as most people use 1, 6, and 11, and 13 isn't far enough from 11 to save you from other user inteference.

      No, but 14 would be far enough from 11.

      I operate mine on ch 9 since most people around me are using 6.

      • Re:It's hardly a secret (Score:5, Informative)

        by Martin Blank ( 154261 ) on Wednesday May 03, 2006 @10:39PM (#15259490) Homepage Journal
        Note: Channels 12, 13, and 14 are illegal to use in the United States.

        You're overlapping, then. Channels are 22MHz wide -- 11MHz on either side of the channel's frequency. Channel 1 is centered on 2.412GHz, channel 6 on 2.437 GHz, and channel 11 at 2.462GHz. Notice that the high end of channel 6 is 2.448GHz, and the low end of channel 11 is 2.451GHz -- a mere 3MHz apart, and subject to some overlap because the 22MHz spread isn't perfect, and bleedover is common.

        Now, in your case (channel 9), you're operating 11MHz left and right of 2.452GHz. Your bottom range (2.441GHz) is just above the middle of channel 6 and your top range (2.463GHz) is actually above the center of channel 11. In addition, channel 9 is also right about the frequency used by microwave ovens, according to Joshua Wright (whose name you'll see on plenty of wireless security tools), and many inexpensive microwave ovens leak enough radiation to poison connections.

        This is all on top of the change coming with 802.11n, which uses 40MHz ranges, many of which may default to channel 6 out of habit, though 3 and 9 will be better selections based on legal bandwidth, and their use of channel 9 will probably swamp your little 11g unit.

        Basically, you're using possibly the worst frequency set you can possibly select.

        • This is all on top of the change coming with 802.11n, which uses 40MHz ranges, many of which may default to channel 6 out of habit, though 3 and 9 will be better selections based on legal bandwidth, and their use of channel 9 will probably swamp your little 11g unit.

          That is not the way I read it. 802.11n uses a 20MHz channel twice, banking on phase differences and multipath reflections to sort out which part of the signal came from which transmitter. This is that "solution to spectrum scarcity" that c

          • That may well be, since I've not read anything especially detailed on the mechanism, and I'm not willing to pay the money required to see the actual draft. My knowledge comes from a combination of what I've read and something I heard from an engineer in the wireless industry (though he admittedly had not had hands-on experience in the spec at that point). However, it does nothing to ameliorate the effective three-channel selection (1, 6, 11) that we now have in place; all it does is preserve that space fo
        • In addition, channel 9 is also right about the frequency used by microwave ovens, according to Joshua Wright (whose name you'll see on plenty of wireless security tools), and many inexpensive microwave ovens leak enough radiation to poison connections.

          One data point in support of that: microwave.jpg [speakeasy.net]. This is a long-term max-hold plot; most of the trace in channel 6 is my WiFi connection, about eight feet away from the analyzer's antenna. *All* of the crap near channel 11 is leakage from the microwave in t

  • don't screw around (Score:4, Informative)

    by Yonder Way ( 603108 ) on Wednesday May 03, 2006 @10:10PM (#15259355)
    If you mess with your WAP to operate outside of legal bands, there is an excellent chance a local ham radio operator will track you down and submit a couple of pounds of evidence to the FCC (or other regulatory body if you are outside of the US) which could (and sometimes does) result in a nice fat fine.

    Your access point has limits for a reason. Please respect them. If you start pissing all over someone else's hobby with your computer junk, they're licensed and you're not, you're the one in the wrong.
    • If you think the FCC actually tracks down violators, you have another thing coming. In reality, you can get away with a lot before the FCC is going to do anything. It's next to impossible to get a jammer off the ham bands (I've tried), and I REALLY doubt the FCC will bother investigating complaints about operation in the ISM bands. They don't give a shit.
      • The FCC doesn't do much at all to track down violators. But hams and scanner buffs do. If the FCC is presented with evidence, they usually will act on it.
      • You are lucky to have a ham band interference problem at all!
        Here in the Netherlands, we lost the top (2400-2450) part of 13cm last year, to protect those poor accesspoint owners that were trampled by the hundreds of watts ERP the hams were allowed to transmit there :-(

        6cm will probably be next. Some of the 802.11a channels are in the ham band as well.
      • Nah, all they have to do is say that you're somehow using it to show boobies, and the FCC will be all over you.
    • Your access point has limits for a reason. Please respect them. If you start pissing all over someone else's hobby with your computer junk, they're licensed and you're not, you're the one in the wrong.

      My "computer junk" actually has some use in the modern world. Ham radio has gone the way of the dodo, and for good reason. Oh, wait, let the protests of "during Katrina, hams did foo, bar, and bat!" begin. Boo hoo. And I can transmit an SOS using sparkgap, but I don't see anyone trying to protect that o
      • Well, hams invented or greatly refined most of the technology used in your computer junk. A ton of radio and electronics innovations were made by hams, and ham radio has and continues to inspire kids to go into electronics and engineering.
        Ham radio in the US is becoming less useful to some extent, but it's still an important form of communications in some repressive areas of the world.
        • And do those repressive areas of the world include the US or Canada?

          Ham radio in North America is a hobby. Something done for fun, that has no actual practical value. WiFi, on the other hand, is useful. Be it aiding a homeowner in networking computers in different rooms, or sharing data among doctors in a hospital, WiFi actually does something useful. The same can't be said about Ham in the US or Canada.

          Besides, it isn't like there aren't alternatives to Ham radios. In the US and Canada, there aren't many p
    • If you mess with your WAP to operate outside of legal bands, there is an excellent chance a local ham radio operator will track you down and submit a couple of pounds of evidence to the FCC (or other regulatory body if you are outside of the US) which could (and sometimes does) result in a nice fat fine.

      The FCC normally sends a warning letter first.
  • Every time I scan channels 12-14 (in the US), I've never found anyone using it. I happen to live about a block from UCSD (the school that I graduated from and where I'm now a research staff member) so this is relatively surprising. I have to admit I've considered it; launching kismet from where I'm sitting on my couch I can detect well over 20 AP's; however on my 802.11A card I can't see any so it's easier (and a lot more legal) to just use the 5GHz band.

  • 1 and 6 and 11 (Score:2, Informative)

    by yttrium ( 88756 )
    The channel bandwidths all overlap, but every fifth starts a new piece... So 1, 6, and 11 are all completely disjoint bandwidths and will not interfere with one another. If you use 8 and 6 in the same area, they will interfere.

  • Just use 11a, if you can (Score:5, Informative)

    by Bretai ( 2646 ) on Wednesday May 03, 2006 @11:34PM (#15259702) Homepage
    Products sold in the U.S. will generally fix the behavior to conform to U.S. rules, and if the Country Code can be changed at all, it probably won't change the operation to add more channels or more power. APs from countries other than US and Japan are usually more flexible.

    Some differences:
    FCC(US) limits average tx power to 27dBm on 1-11
    ETSI(Europe) has a limit of 20dBm on 1-13, although individual countries could add further restrictions.
    MKK(Japan) 20dBm on 1-14

    In 11a, there are greater differences:
    FCC - 17dBm on 36,40,44,48, 23dBm on 52,56,60,64, 30dBm on 149,153,157,161,165
    ETSI - 20dBm on 36-64 and 27dBm on 100-140
    MKK - 23dBm on 34,38,42,46 and possibly 20dBm on 100-140 plus a few other odd lower channels.

    The actual rules are too extensive to list and they're constantly changing. If you have an older 11a Access Point, you might only see channels 36, 40, 44, and 48 available. Another big factor to consider is DFS. DFS applies to channels 52-64 and 100-140. It requires the AP to switch channels immediately when it detects a radio signal that might be Radar, and the user is not allowed to return to that channel for 30 minutes. Client devices must passively scan for APs and APs must scan the channel for radar for 1 minute before starting operation on that channel. The US is adding DFS requirements in July 2006. Fortunately they're adding the 100-140 channel range at the same time, so it's not all bad.

    You might think that the upper channels (149-165) are ideal for higher power and no DFS, but I think that is the range that get interference from 5.8GHz cordless phones. I'd go with 52-64 pre-DFS rules. 11a has less range, but that also means less neighbor interference. There is less channel overlap. No microwave oven interference. There are no 11b stations to trigger 11b protection modes, or God forbid, a concurrent 11b user on the same AP as you. Most importantly, there are still fewer users of 11a. Where I live, I have neighbors across all of the 11b/g channels, but just a couple on 11a, so I can find an unused channel all to myself. This is much more important than any B.S. Speedburning, RangeMaxing, Super features which have always under-delivered with performance.

    Anyway, I think you can see that the U.S. rules are pretty good, so there's not much reason to set the wrong country and violate FCC rules... unless you like that sort of thing.

    • DFS is no fun... after you have carefully determined the channel with the lowest background noise level and enjoyed good communication for days, a sudden spike of interference (lightning?) makes the AP jump to another channel. This might be a noisy, busy channel, but the AP will stay there until it gets another spike, which may take days.

      This probably is implementation-dependent. It could be a good thing when the AP attempts to go back to the selected channel after some time, and/or a number of channels

  • 802.11d (Score:2, Informative)

    by hockeydude ( 972716 )
    The country codes are related to the 802.11d addendum. 802.11d is for International Regulatory Domains. It provides a mechanism to allow subscriber stations to automatically detect the country that they are operating in and limit their maximum transmit power accordingly. Each country's regulating body (like the FCC) sets limits on transmit power for different operating bands. If you look around, you'll discover very little consistency from country to country. It's a regulatory nightmare, really. An AP
  • if you're in the UK and expecting US visitors to your wireless network you would be well advised to avoid using channels 12-14 since US wifi cards won't see your wireless router

Slashdot Top Deals

"Protozoa are small, and bacteria are small, but viruses are smaller than the both put together."

Close