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The Internet

High-Speed Multimedia Hamming 212

Posted by michael from the dit-da-dit-dit-dit dept.
Skuld-Chan writes "I noticed a few days ago that the ARRL (Amateur Radio Relay League) formed a working group to promote use of 802.11 protocols on the amateur radio bands."
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High-Speed Multimedia Hamming More

High-Speed Multimedia Hamming

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  • woohoo! (Score:2, Interesting)

    by vorovsky ( 413068 )
    Oh wow, this is GREAT news for me! I've been a radio operator for about 7 years now and tried to dabble a bit in the "data links" before the days of 802.11 at all. Just recently I had a renewed interest with all of the 802.11 products but was having a hard time integrating them into ham radio more. Woohoo!
    • Part of the reason that I obtained my license in the first place was to be able to play with some of the more interesting tech. Several of us gather at a local restaurant, about two miles from my home, and I've wanted to set up a bi-directional link to allow us to have high-speed (or at least better than 56K) internet access while we're 'geeking'. If equipment becomes easy to buy or build, this'll finally be a reality. yay.
  • I am actually looking for a way to get wireless access to my personal network a safe (secure) and legal way. I just want internet and access to my network in my car or wherever I may be in the general area of my house.

    Anybody know of some good cost effective methods that do this?

    • Re:I was wondering (Score:1, Insightful)

      by Anonymous Coward
      Remember part of the FCC rules for hams state that no-encryption shall be used. I dont know about you, but I dont like broadcasting my internet traffic over the air without encryption.
      • Remember part of the FCC rules for hams state that no-encryption shall be used.

        Which means 802.11-over-ham is not going to be useful for personal connections, and only usable for information that's suitable to be broadcast.

        • Re:I was wondering (Score:2, Informative)

          by gasp ( 128583 )
          Except part 97 does not permit broadcasting. :) Seriously, I see almost no potential for using 802.11b in any normal way on the ham bands. The story says they hope this will encourage existing part 15 users to get amateur licenses and operate under part 97. I just can't see any practical motivation for this.

          Remember, ham comminications must not be encrypted. They must not be commercial. (This means no ads, no non-ham commerce, basically no websurfing.) They must not be broadcast. (Not really a problem, not much different from packet radio this way.) Each transmitter must identify itself. (I suppose using the ham callsign as the SSID would work for that.)

          Sure, hams can have fun playing with 802.11b under part 97, but because of the content restrictions it's in NO WAY any replacement for the people operating under part 15. Seriously, how useful is a network connection that is not allowed to be secure or be used for commercial traffic.? Yes, it has potential for ham-related events, contests, and emergencies. But I don't see anything else.

          One peeve of mine is that hams have become followers and are no longer leaders in radio technology. There was a time when hams did things first, and commercial radio products and services grew from those efforts. Technology has mostly become too complex for the single hobbyist to provide a substantial development contribution. Now the ham community mostly waits for commercial technologies to become old and inexpensive, then adapts them for their own purposes while adding little or nothing new. A large part of the reason hams are allocated valuable spectrum is for innovation, but in the past decade I've seen only regurgitation. I would love to use my ham license to do something I couldn't do more cheaply and effectively on the commercial bands. 802.11b under part 97 is another example of less functionality for more effort.

          I'm not saying it's not worth doing, just that it's only useful to the hobbyist who wants to play and do a thing because it can be done. I'm saying it's not useful to anybody who wants to operate a real and practical wireless network.
  • This is what I do at Subway at lunch. Then I rush back to Slashdot.

    (ducks)

  • This is bad news (Score:2, Insightful)

    by luckybob83 ( 530490 )
    If you read the whole article you will find that they actually want to boot the unlicensced people out and get it all for the licensed HAM operators. This is bad for all the WISPs out there, and then also there go my plans.
    • It really isn't that hard to get a HAM license. If there is a local HAM club in your area they usually perform tests on a regular basis. If you're serious about it, look into it.

      On a side note, when we were doing this stuff in college for a project, they weren't too sure about all the wireless stuff taking up channel space. I'm not sure if they are against it by now or not?

    • Re:This is bad news (Score:4, Insightful)

      by GlassUser ( 190787 ) <slashdot@glassuG ... r.net minus poet> on Wednesday January 15, 2003 @10:58AM (#5087488) Homepage Journal
      I really don't care for the whole WISP idea. I don't believe that it's proper to be using public resources for personal (or even worse, corporate) profit. If the WISPs want to have a for-pay service, then they can participate in the band auctions just like the TV stations and cellular carriers.

    • Re:This is bad news (Score:2, Insightful)

      by Mr2cents ( 323101 )
      Erm.. I don't get your point. wat is 'it'?? You always need a ham licence to access ham networks, it's logical since your actions activate transponders that require a ham license.
      Ham's are allowed to use 2.4Gh, but so are you (you just have to use licenced transmitters, hams can build them theirselves).

    • Re:This is bad news (Score:2, Insightful)

      by Nate B. ( 2907 )
      Well, for the several channels of 802.11b that utilize the Amateur Radio Service allocation in the 2.4 GHz region at least, the users of those Part 15 devices must accept all interference from licensed service operations and not cause harmful interference to those same licensed users. This is long-standing FCC rule policy in the U.S.A.

      For several years we Amateur Radio Operators have lived with the spectre of manunfacturers dumping all sorts of product onto the market obstensibly operating under Part 15, but causing all sorts of problems to licensed users. Of course, the manufacturers conveniently forget to inform their customers of the pitfalls of relying on a Part 15 device. So, when a licensed user's operation is harmful to the device, the customer naturally holds them to blame as a result of ignorance. Slowly the noise floor (a measure of how weak a signal one can receive from a distant station) has increased, so we hams are naturally, looking to get *our* spectrum back.

      The WISPs should be required to operate in a properly licensed and allocated Service, IMO. Part 15 devices are intended to be small operations that cover a house, small business, etc. NOT as a wireless urban LAN. AFAIAC, WISPs should be considered in the same way as cellular providers.
      • Let me see if I understand your position. Hams, numbering in the thousands, maintain that part 15 users, numbering in the millions and growing at double digit rates annually, should stand aside. Nascent metro area networks, should be cut off because they may carry traffic which is encrypted, commercial or obscene.

        Obviously it doesn't make sense to mix what has the potential to become a mass media service with amateur uses. Why would it be in society's interest to hobble a service on this scale for one as limited in utility as part 97?
    • You're right about the hams but practically speaking, it's little or nothing to worry about.

      Hams are growingly concerned about their spectrum getting usurped (and rightfully so, it has happened before and the ARRL is constantly fending off new threats). Part of that sentiment has an outlet via reminders to spectrum users lower on the 'totem pole' that hams have higher status.

      IIRC, the 2.4 GHz ham band extends from 2390 to 2450 MHz. (They used to have 2300-2310 or so too, but it's gone.) However, the FCC Part 15-247 unlicensed band extends from 2400 to 2483.5 MHz. This means that the upper 5 or so 802.11b channels are out of the way of hams that might be operating in their licensed band. High power ham radios in that 2390-2450 slot *shouldn't* be emitting much energy outside it, but even a little can cause interference to 802.11b radios operating above 2450. Summary: almost half the unlicensed 2.4 band the hams cannot touch but that doesn't mean there would be no problems.

      There are also strict rules on how hams can use their spectrum. A *LOT* of what unlicensed users can do in the way of data transfer (almost anything goes) is prohibited for hams. Anything that facilitates a business is out. Another big one is the issue of unlicensed operators causing emissions of a ham radio (they basically cannot). The regs are a bit vague but that's the gist of it. The result is that the only legally 'safe' manner in which to operate is to talk only to other hams over such a licensed link.

      I am a licensed ham - have been since I was 9 years old, yet feel sad when I read the article. It used to be hams were on the forefront of developing new radio technologies (indeed, that's one of the tenets of the amateur radio charter - furtherance of the radio art) but here I see them (us) glomming onto technology mostly developed in the commercial sector, and threatening to push unlicensed users out. Hams still have a boatload of frequencies available, especially in the microwave regions. However, most of us don't want to take the time to design new radios. You get the picture.

      Even though I could legally use an 802.11b radio at high power, etc., I'd rather operate unlicensed and not be subject to restrictions on what traffic passes over a link. My Internet connection at home is via an 802.11b-based provider.

      'nuff said.

      • US hams are still authorized [gpo.gov] for 2300-2310 MHz. See the ARRL band plan [arrl.org] for the 13cm band. Actually, we used to have all of 2300-2450 in one big 150 MHz chunk. But 80 MHz of it has been lost, so it's now 2300-2310 MHz (mostly because that's where the DX work was done, although it does include things like repeater inputs input so as to have a wider frequency split) and 2390-2450 MHz. Hams do not have 2450-2483.5 MHz, so any operation there has to be strictly under Part 15 [gpo.gov] rules, including things like not interconnecting any Part 97 [gpo.gov] operations.

        US Hams still have all of 5650-5925 MHz in a single 275 MHz chunk [arrl.org] in case you might be interested in working some 802.11a [google.com].

      • I am a licensed ham - have been since I was 9 years old, yet feel sad when I read the article. It used to be hams were on the forefront of developing new radio technologies (indeed, that's one of the tenets of the amateur radio charter - furtherance of the radio art) but here I see them (us) glomming onto technology mostly developed in the commercial sector, and threatening to push unlicensed users out. Hams still have a boatload of frequencies available, especially in the microwave regions. However, most of us don't want to take the time to design new radios. You get the picture.

        Bingo! I've been a ham radio op since I was 13, and this year will be my 14th with a ticket. 73 de VE1SFM. Back in the day, you used to see all sorts of problems with digital modes and packet radio mixed with the internet. People freaked, because the internet was seen as a threat. I was into that for a long time. How many of shops even have homebuilt gear in them? I have some stuff, but mainly accessories, power supplies and antennas. Everything else is commercial. It seems more and more people rely on commercial stuff from companies like Kenwood, because it's reliable and inexpensive realative to developing your own. That's not why ham radio developed as a hobby, though.

        Along comes 802.11. Hams should be embracing spread spectrum technology and pushing the envelope. The design of this technology is hard, and it's already available to anyone. The genie is out of the bottle with 802.11 though - the fact I can go in and buy this hardware for $100 is absolutely mind boggling. People should be looking for ways to extend and modify this gear, looking at ways to get into making custom digital chips to change the modulation schemes, etc etc etc.

        If you told me I could go buy a SS radio w/10mbit bandwidth (let alone 54mbit) with a computer interface for $120cdn 10 years ago, I would have laughed in your face. That was science fiction, the stuff of star wars satellites.

        But, no, instead what I see here is the ham radio organizations trying (hopelessly, I might add) to kill or restrict one of the best things to happen to public communications since Marconi flew a kite. Or tesla made a coil :). Anyone who doesn't like seeing city-wide lan's spring up based on this technology.. well, THEY should go fly a kite.

        Bah, humbug.

    • The overlap between the ISM band and the amateur 2.4 GHz band is only partial.

      a) While hams have legal rights that place Part 97 users above Part 15 users, hams are usually more intelligent about causing interference and more responsible about solving it. I.E. while a ham legally doesn't have to solve an issue of a Part 97 interfering with a Part 15 device, he usually will try to help with the problem. (Many hams will readily supply their neighbors with interference filters if they complain that the ham's HF rig is causing TV reception or phone problems.) OTOH, Part 15 users are usually assholes about fixing problems even though they are legally required to.

      b) Hams can legally operate 2.4 GHz equipment outside of the ISM band. Trust me, if they're able to, they WILL to avoid the Part 15ers. Getting equipment that will operate like this can be tough though - I've only heard of it being done with Proxim equipment, who would sell you WLAN gear that was designated for the Australian ISM band (which overlaps the US amateur band completely) if you faxed them a copy of your license.
    • "If you read the whole article you will find that they actually want to boot the unlicensced people out and get it all for the licensed HAM operators. This is bad for all the WISPs out there, and then also there go my plans."

      I got my Ham license when I was 10 years old. And back then, I had to learn Morse Code to do that. Today, it's almost too easy to get it.

      Given what you learn from becoming a Ham operator, I'd say it's worth it. You need to know how radio works if you're going to deploy WISPS without interferring with each other.
    • You need to re-read the article because it says nothing of the sort. The hams are trying to get primary access to I believe 2mhz of the band, which is next to nothing, and in any case, has nothing to do with their 802.11b efforts (it is for narrowband satellites). By and large, what they (The HSMM) is GOOD NEWS for part 15 hackers, who are now operating in a gray area. They (the part 15 hackers) have much in common with the roots of ham radio. I think this is a very good thing. And it is not much of a problem for a real WISP, because the population density is so small in the rural areas a real WISP would operate in. The only time a part 15 user has to defer to a ham is if they cause interfernce to communications on a ongoing base, and the times this has happened can be counted on one hand. The sky is not falling.

  • Replacing the internet? (Score:2, Interesting)

    by KDan ( 90353 )
    I'm not an expert in Ham or this, but I'm curious: is there any possibility, in the medium to long term, for replacing most of the internet infrastructure with an amateur-operated wireless net, free of corporate or governmental intrusion? ie does this technology go in this direction?

    Daniel
    • Sure, but you can't encrypt your transmissions or transmit profanity or obscene materials.

    • Technically, yes. As a matter of regulatory policy, no. Right now encryption is prohibited unless the transmission involves authentication for control operations of another amateur radio station. Otherwise transmissions must not be obscured in an attempt to hide their meaning.

      A spirited debate is ongoing at QRZ.com [qrz.com] over this same topic.

      The fact is that amateur radio is regulated not only by individual adminstrations i.e. FCC in the U.S.A., but also by ITU treaty regulations as well.

      Commercial traffic that is a direct benefit to either of the parties conduction the contact are prohibited as is content of an obscene nature. In short, ham radio is not currently a legal way to provide "last mile" internet. You're still limited to 802.11A/B Part 15 devices for widespread unlicensed use.

    • ...in the medium to long term, for replacing most of the internet infrastructure with an amateur-operated wireless net, free of corporate or governmental intrusion?

      Actually, before the internet became widespread, there was a large network of packet radio users on the east coast. Although it was slow (300bps to 9k6), it is possible. And there's been some work on 10 gHz [qsl.net] broadband radio links. There's also been other bands used, but I don't have links to them.

      The main problem with attempting to do this over the ham bands is the fact that encryption isn't allowed on the ham bands. Compression is allowed iirc, but encryption isn't.

      neurostar

      • I forgot to metion this in my previous post, but there is currently a group working on this idea.

        The Guerrilla.net [guerrilla.net] project is aiming "to provide a networking fabric outside of Governments, commercial Internet service providers, telecommunications companies, and dubius Internet regulatory bodies."

        neurostar
    • There is not enough bandwidth, even if you're dealing with low power short distance sets. Assume you're using a transceiver with a nominal 1 mile range. The signal might be good enough for a digital transmission 2 or 3 miles if conditions are good. However, the signal continues on for a long way past that; too low for a readable signal, but a constant contributor to background static. Most of the static you hear on a CB radio are mixed signals from all of the other CB's on the planet. Back when CB's were rare, you could sometimes hear skip transmissions from other continents. Now you are lucky to hear something 5 miles away.
    • Amateur radio regulations explicitly prohibit the use of the radio spectrum for any sort of commercial activity what-so-ever. It also explicity prohibits the transmission of any information in any form of a ciphered form, so SSL, WEP, etc are all illegal on amateur bands. You can't even SSH over a packet radio link.

  • Amateur Radio needs to reinvent itself (Score:3, Insightful)

    by ramas ( 48614 ) on Wednesday January 15, 2003 @10:50AM (#5087427)
    I have been an amateur for 11 years now ON and OFF mainly because communication by itself (even the kind of communication that wireless offers!) is now ubiquitous with the arrival of the WWW, cell phones and sat. phones and so on. However, I believe that wireless has its own space and needs to reinvent itself. 802.11 is a great opportunity to bring out the spirit of amateur radio which is more about experimentation and exploration of our environment than just about those rock solid 59+ 40db signals from your cell phone.

    lets hope that this effort provides a new lease of life to the now ailing (in terms of activity and numbers) hobby.
    • IANAH (I am not a Ham) but...

      How can this promote or invigorate amateur radio at all? I have had the opportunity to explore the world of amateur radio with friend's equipment and I believe I have a fair understanding of the prinicples involved, but I cannot for the life of me imagine any opportunities granted through the use of 802.11 that are not already available.

      I have "played" with Shortwave on a 15-25(I forget) meter antena and spoken to the Ukraine, it was crap and barely destinguishable. I have also "played" with the IRLP [irlp.net] (a project I would have expected /. to embrace ages ago, since it is bringing new people to Linux daily by providing an actuall use for average pc users) and found quite the opposite. On a little mobile car radio I was able to speak clearly to the UK and Australia as though I was using a really high quality cell phone service.

      So what exactly does this project do to "reinvent" Amateur Radio that is in any way more attractic/effective/efficient/etc. than the IRLP which has already been around for years and has relays now all over the world?
    • I dont generaly do "me too posts, but I will in this case. I got my amateur license in 1993 because I wanted to do TCP/IP packet radio and I wanted my home on the Internet (not easily done at home in '93). Back then, the main uses were e-mail, telnet, and USENET news. None of the bandwidth hogging rich content so common today. So AX.25 with 1200 baud and later 9600 baud was fast enough.

      I'll admit that my interest has since waned. My fastest digital gear is still 9600 baud, and while it is quite easy for me to communicate over 60 miles, 9600 baud doesn't cut it.

      The emergence of some high speed spread spectrum stuff is pretty exciting. I will probably renew my license this year so I ca be ready to get involved. Wireless broadband over wide areas appeals to me.

      Its strange how ham radio was leading-edge in wireless networking a decade ago, with pioneers like Phil Karn (KA9Q) actually contributing to the specification of the TCP protocol itself as a result of his packet radio experiements, to now, where it has been sitting well behind the part 15 world. I hope this exploration brings the hobby back to the innovative levels of 10 years ago and brings some new hobbyists in.

      73 DE N0ZES
    • [Ham radio is dying because] communication by itself is now ubiquitous with the arrival of the WWW, cell phones and sat. phones and so on.

      This is ABSOLUTELY TRUE. The Internet has been eating amateur radio's mindshare lunch. The demographics of ham radio has been steadily moving toward the elderly end of the curve.

      One of the original functions of ham radio was to provide a venue for communication innovation. I would love to see this function find its rebirth in growing 802.11 connectivity. Maybe hams can build the big Wifi blanket that everybody talks about. It would also line up with the ham charter to provide emergency communications.

      What would really be interesting would be to see hams go in novel directions of radio experiments: things like antennas even more interesting than the Pringle can, and different modulation schemes... lots of interesting possibilities.

  • This sounds very cool. I'm assuming ARRL expects to see 802.11 replacing the existing radio data systems, packet radio and such?

    What are the advantages to using 802.11 on the amateur bands, versus the already allocated frequencies being used by WiFi products? Longer range? Anything else?

    • The big advantage would be speed. Packet radio is slow. 1200baud is still the norm on the 2m band.

      The bandwidth of 802.11b is too much to be run on any of the VHF bands, but 70cm (440MHz) or higher may be plausible. I envision the first efforts no on 2.4GHz involving a transverter (which would convert 2.4GHz down to something else for transmission, and back up for reception)

      As for usage of the existing 2.4GHz band, I regret to inform the unlicensed users that radio amateurs had greater legal access to the band well before 802.11 came along. We have a secondary allocation to part of the band, and primary to another part. Unlicensed users, using the band under the part 15 rules, have no rights whatsoever. Even so, I see no reason why we need to go chasing each other around the bands, and I disagree with the point of view that was expressed in the ARRL article. You might, though, as a courtesy to us, pick a channel above 5, since only 1-5 can be used uner part 97... where they can be used with linear amplifiers quite legally (again, assuming the user is in posession of a license).

      Regarding this system replacing the internet.... I am not certain that ham radio can do that. My main concern is the fact that we cannot carry messages for hire, nor can we carry any sort of commercial traffic (a single pop-up, spam, or ecommerce site would cause a legal problem). What will make things interesting is that it will be possible for someone with an unlicensed rig to communicate with someone using a high-powered licensed rig. This will mix up the rules a bit and I'm not sure what the end result will be....

      • In addition to channels 1-5, hams have access to frequencies "below" channel 1.

        To use this, unfortunately, it will either require firmware hacking or a company being nice and shipping Australian-designated 802.11 equipment to US hams who show their licens (like Proxim did)
    • How about a Medal of Honor tournament spanning several miles without the use of dial up and typical Internet lag?

      The data is probably not encrypted and your player name or machine name can be your callsign to appease the FCC rules on identification.
  • Just what most wireless people want, more traffic at 2.4 GHz. It's amazing how much traffic goes on at that bandwidth. I'll be glad when new frequencies are opened up for commercial use. We had quite a few 2.4GHz wireless radios that in many locations couldn't get a solid signal because of interference. We ended up switching to 5.8GHz in some locations to deal with the interference. It's for this reason I'm glad we dropped wireless, and went to phone based.

  • We just discussed this last night in HWUG (Score:4, Informative)

    by Brento ( 26177 ) <brento.brentozar@com> on Wednesday January 15, 2003 @10:53AM (#5087453) Homepage
    Houston Wireless User Group [houstonwireless.org] just discussed this as our presentation for last night's monthly meeting, oddly enough, complete with a very nice presentation [houstonwireless.org] by Erewhon.
  • So, is this a bandwidth grab of internet users from ham radio? The soviets were bad enough with their "woodpecker" jamming frequencies; if every computer owner with a spare hundred dollars starts broadcasting data on ham frequencies my grandad won't be able to call out "cq cq cq" much longer :-(.

    Of course if it is in a new separate band, that's something else.

  • Why ham? (Score:1, Interesting)

    by PhysicsGenius ( 565228 )
    I understand why they used to do it back in the 50's--there wasn't much other way to talk to people far away, plus radio technology was still cool back then. But with the rise of the Internet and the replacement of vacuum tubes with computers in the hearts of true geeks, why does anybody continue hamming anymore?

    • Re:Why ham? (Score:5, Insightful)

      by oldave ( 160729 ) on Wednesday January 15, 2003 @11:16AM (#5087619)
      Recent examples... when the federal building in Oklahoma City was bombed, the public switched telephone network (including cell phones) was overloaded in minutes. Ham radio was the only reliable method of communication.

      On 9/11/2001 in NYC, within moments, the public switched telephone network was overloaded. Ham radio was the only reliable method of communication.

      In areas hit by natural disasters such as hurricanes, ham radio is often the only method of communication that works.

      You see, ham radio operates on many frequencies, from local, line-of-sight to world-wide reach. In times of emergency, when other methods of communication fail, ham radio operators are there, with their batteries, radios and sometimes jury-rigged antennas to get word out about what may be needed in the area, also information regarding the health and welfare of others.

      • Re:Why ham? (Score:2, Interesting)

        by AvantLegion ( 595806 )
        Those examples are interesting, but of seemingly little use.

        What is the overriding importance of having the "only reliable method of communication" during Oklahoma City, or 9/11?

        CNN, Fox News, etc., told me that planes slammed into the towers. I didn't need a Ham radio for it.

        Perhaps you're implying that the important thing is to communicate about other things during those times, but I sure didn't find myself feeling cut off or devoid of means for important communications during those times.

        I can see the use of Ham if we're, like, invaded by China, or Raelians and their extraterrestrial buddies, or something like that. But I don't see any real useful advantage of Ham in those other examples.

        • Re:Why ham? (Score:2, Informative)

          by gekman ( 224336 )
          In the hours/days after the WTC attacks, most of the cellular phone infrastructure in lower Manhattan was dead, not simply overloaded. During that period ham communications aided many agencies begin the rescue efforts, including fire, police and the Red Cross. Most of these agencies' radio equipment operated on non-compatible frequencies, so even though their radios were working, they could not talk to other groups. Many hams volunteered as "shadows" who stayed with officials of the various agencies, allowing them to talk with other officials via ham frequencies. This lack of interagency communications still exists today, although the problem is being addressed at the local, state and federal levels.

          George/W2GEK
    • It's just like anything else. You could blow your money on computers, HDTV, cars etc. Amateur radio has been around a long time and I enjoy it as much as working with linux, solaris and Sun boxen.

      When the internet goes down and or the cell phones quit working, I can always depend on amateur radio to pass the traffic when all else fails. Ham radio was used during and after the world trade center attack because all regular communications systems were not operational (public service, cell phones, etc).

      There's nothing like the thrill of working a distant station on HF under less than ideal conditions. It's like the thrill one would get after hacking a government computer, and giving yourself the refund you deserve ;p
    • Because it's fun, of course.

      The young often forget that something doesn't have to be cool to be fun.

  • 'regular' 802.11 networks in danger? (Score:4, Insightful)

    by hcdejong ( 561314 ) <hobbes@@@xmsnet...nl> on Wednesday January 15, 2003 @10:55AM (#5087462)

    A radio amateur with an 802.11 transmitter could easily jam the low-power, shitty-antenna transceivers used in 802.11 networks. Only a few channels (up to 14) have been defined for 802.11 use, and it only works because transmitters have limited range. Change that, and you've got instant DOS.

    • Is there much a determined radio amateur couldn't jam?

      It rarely happens on purpose. Causing intentional harmful interference is a big no-no in amateur radio. It's against the spirit of the hobby, and quite illegal in most places. Among other things, the amateur radio rules require a specific receiving party; you can't just transmit garbage for no reason.

      That said, part 15 devices must accept harmful interference from properly licensed non-15 devices. If a receiver can't handle a nearby signal from a device operated legally under part 97 (with proper identification, power output, receiving end, etc), too bad. Get a better receiver or petition the FCC to open up more frequency space to unlicensed low-power devices. I think that's the real solution.

      -John, KG4RUO

      • It rarely happens on purpose.

        True. But the problem here is, if the performance of your 802.11 network takes a nosedive, how are you going to find out that it's due to a radio amateur jamming your signals?

      • Is there much a determined radio amateur couldn't jam?

        You bring up a good point. I knew a guy when I was first getting into amateur radio that liked to talk to people at the local McDonalds through their headsets. He only did it a couple of times and it seemed harmless but I guess if everyone did this, it would be quite a mess. What he would do is wait until just before closing and then sit up on the hill and talk to them saying something such as "This is God. *long pause* I want a whopper. *another pause* I am in the pink Caddy out front. Then he would just watch the people freak out.

        Another buddy took his radio with him on a high school band trip and talked through a tv in another room of the hotel while it was not turned on. Caused one girl to start crying because she thought the tv was posessed. So yea, you can jam pretty much anything. If you use the right frequency and enough power, you can shut off a modern car, start things on fire, etc. That's why amateur radio licenses used to be a bit more difficult to get. Now that you no longer need to learn Morse code, all you need is some basic electronics knowldege and a few evenings to study and your ready to take the test and get your license.

  • I always felt that with all other stuff that was crammed on the bird, it would have been nice if they stuck an 802.11 access point on board. Of course, we'll never know if it would have survived the "event" that occurred shortly after launch.
    • I always felt that with all other stuff that was crammed on the bird, it would have been nice if they stuck an 802.11 access point on board. Of course, we'll never know if it would have survived the "event" that occurred shortly after launch.

      Well, there certainly are modems and computers on board. The RUDAK experiment is slowly being cranked up as the control operators (carefully) prepare to try to put AO-40 in 3-axis stabilzied mode. Digital networking though AO-40 is still part of the plan, as far as I know. I don't think 802.11 would be a very good idea in this environemnt, though; there are other protocols better suited.

      The "event", for those who don't know, was a small explosion on board the spacecraft as a result of problems with the liquid-fueled rocket engine. AO-40 has only a fraction of the capabilites it was intended to have as a result. Nonetheless, AO-40 is used every day in a variety of modes, and digital comms though AO-40 are still very much on the agenda. see http://www.amsat.org for more information.

      --Maggie K3XS--
  • I was at the Houston Wireless Users Group (HWUG - http://www.houstonwireless.org/ [houstonwireless.org]) meeting last night and this was our primary topic. One concern we had was stations supervised by licensed operators and classed under Part 97 communicating with Part 15 Unlicensed (eg Joe Sixpack WiFi APs) stations. I believe the consensus is that you're not supposed to communicate like that, but I don't think anyone has proposed effective access controls for it. Any suggestions?
    • for those who dont 'get it' (like me) why would you WANT 802.11 on Ham Radios? why not just stick w/ PCs and 802.11b APs (as we have now)?? multimedia on a radio? umm, wouldnt a wireless 802.11b tcp/ip network do that..?

      what is the point? sorry - i just dont get it..

      • Probably the biggest attraction is more flexibility. You have a lot more leeway with putting together "systems" (currently, to operate under Part 15, you technically have to have your entire system - transceiver, cabling, and antenna - certified together). With a licence, you're considered more responsible and somewhat less subject to rote as opposed to making sure you don't exceed your signal max spec. Also, you could transmit in that band in up to 100 watts, whereas "powerful" Part 15 equipment is only at 200 milliwatts.
      • Power and distance. Ham radio operators can transmit up to 1500 watts PEP and can have as big of an antenna as they want (limited only by FAA regulations and local zoning regulations). Part 15 devices are limited to 1 watt (I believe) and must use those teeny antennas that come with the device.
        • Part 15 devices such as WiFi are actually limited to miliwatts depending on the antenna used. Most commercial devices only output 30-100mW. An opporator with a Basic Amature license, which is easily obtained, is probably limited to about 100watts. An Advanced license would be required for higher power. Although 100watts is still enough to cook a bird.
          • Thanks for the info on the part 15 devices. My 1 watt estimate was an upper bound.

            According to Section 97.313 [arrl.org], there is no license class restriction on the power output allowed on the amateur microwave bands, making the limit 1500 Watts regardless of whether you are a technician class or extra. However, it also states that you must use the minimum power necessary to maintain reliable communications. My 5 watt 2-meter handheld is perfectly sufficient if I am on a hilltop, and my 50 watt mobile is more than adequate on level ground. So a 100 watt limit is probably a reasonable expectation both from the minimum power rule and a technical point of view, unless you are trying to bounce your signal off of the moon.

            • According to Section 97.313

              My bad. I was going from memory. I should have really looked that up. Another poster wrote that there is a limitation of 100w on spread spectrum signals. At any rate you can already push 802.11b pretty far with decent antennas and the existing low power levels. The limitation seems to be the curvature of the Earth.

              As an aside I am no antenna expert, but I cringe every time I read a story about some point to point link useing WiFi. They are willing to buy nifty cards and access points, but when it comes to antennas they often use high loss cheap coax instead of $1US/ft for nice lower loss LMR400. And some of the hacked together antennas are so hideous it is a wonder they work. There are some good and really good DIY 2.4GHz directionals out there, but the awfull pringles can is not one of them.
    • You can use ANYTHING on the Ham bands as long as:
      1) YOU, the control operator, are licensed for that band.
      2) The equipment you are using meets the part 97 emission requirements.
      3) You are not violating any of the usage rules.

      If you want to use a part 15 WAP on the ham bands, you are perfectly legal so long as the equipment isn't spraying all over the place, you properly ID every 10 minutes, you are not encrypting the traffic to prevent monitoring, you are not sending commercial traffic, etc.

      The fact that the WAP is part 15 in and of itself does not matter.

      That said, I don't know how you would meet the ID requirement - most WAPs don't know how to send Morse, and I don't think sending out an ICMP with your call sign embedded in it would be acceptable.

      • Yes, but the concern was that the usage rules state you can't broadcast to the general public. I believe that was the part that snagged us.

  • I wouldn't mind being able to create my own WiFi network without having to purchase the $100 a piece accessories :D,/p>

    I do think that it's interesting to see people who usually work with HAM stuff to move into trying, and succeeding apparently, to make WiFi work with stuff that they've put together.

  • Maybe I am not getting it but you have 802.11 in ad-hoc mode and what do the ham folks want besides that?

    You also have the stuff from locust world [locustworld.com]for mesh networks.

  • from the dit-da-dit-dit-dit dept (Score:5, Funny)

    by Goody ( 23843 ) on Wednesday January 15, 2003 @11:24AM (#5087676) Journal
    Please add "morse code" to the list of things that the editors don't know.

    Goody
    K3NG

  • What's the point? (Score:2, Insightful)

    by Anonymous Coward
    I am a licensed ham, but I cannot help wonder what this should be good for. 802.11 is designed for LANs, and I would expect that it doesn't work well over larger distances (just think of latency times).

    For local use, 802.11 is available to everyone without a license, and hams are allowed to use it like everyone else. If you do it within the amateur radio service, it is subject to pretty stringent regulations - no encryption, no offensive/indecent communications, access only for licensed hams, no communications associated with any kind of business or pecuniary interest (and this is interpreted _very_ strictly); if the communications span a border to another country, even more stringent restrictions apply (no "third party communications" unless there's a bilateral treaty, only "messages of a superficial nature").

    Amateur radio isn't meant to, nor does it work as a free (as in beer) alternative to cell phones, internet, whatsoever. Emulating something within the constraints of amateur radio that is available in a more useful form to the general public anyway is bound to fail. Packet radio activity seems to have died out in many regions, simply because Internet access is so much easier, faster, more versatile, and nowadays more easily accessible. If I want to transmit "multimedia" content (whatever that buzzword may mean), I can do so online.

    I'd really like to experiment with new modes, and that's difficult enough (the regulations on spread spectrum communications are EXTREMELY strict, since the FCC has to be able to monitor your communications). Going through that hassle may be worth if you're experimenting with something new. Carrying 802.11 over to amateur radio is to me neither innovative nor interesting.

  • Remember, anything done as an amateur can't be commercial, so it's really not feasable that these networks could hook up to the internet or otherwise have outside access.
    Rick

  • Emergencies (Score:4, Interesting)

    by gibbonboy ( 162143 ) on Wednesday January 15, 2003 @11:28AM (#5087698)
    As others have said, in a real disaster, the normal public networks are quickly overwhelmed. Amateur operators who can use their networking equipment over longer distances can transmit all sorts of vital information in and out of a disaster area. I am playing with these systems at home, with hopes to have them ready for emergency use soon. More experimentation leads to technical jumps not possible when design is only driven by limited power and profitability for the manufacturer.

    KB3HQX, Susquehanna County ARES Coordinator
    EMA/911 Database Analyst

  • ARRL's real name (Score:2, Informative)

    by LinuxOnHal ( 315199 )
    The posting shows the ARRL's name the "Amateur Radio Relay Legue," this isn't quite right. The ARRL is actually the American Radio Relay League, a National Association, primarily for Amateur Radio operators and interesed parties. It now has over 163,000 members and a staff of 120.
  • Federal regulations explicity prohibit "broadcasting" by amateur radio operators, broadcasting being defined as any radio communication intended for reception by the public, unlicensed operators.

    The only way I can see this working is if they open up new bands for 802.11 communications that are exclusively for the use of licenced amateur operators, the way they have two extra bands for radio control devices for the exclusive use of amateur operators. That would mean likely more expensive hardware, and I'd wonder exactly how the amateur radio community and FCC would police it.
    • Its legal - take a look at part 97.311 - SS emission rules.
  • .. hams will need to do a QSL instead!

    Yes, I know that was quite corny...

  • WOW (Score:2)

    by mnmn ( 145599 )

    I had long planned to build a very long wave radio connection with a radio guy in Pakistan, to connect them to the Internet here. I had been visiting sites to find the best way to encode digital, but this sounds perfect for the job.

    802.11 over radio will also radically increase the area(useable by ISPs) . I can see it now: sitting on a remote mountain deep in Canadas country, with my solar-powered transmeta laptop, playing counterstrike with my friend, deep in the australian outback.

    Cant wait to buy laptops with 802.11 over radio built in.
  • You cannot encrypt ANYTHING on amateur radio bands. so using WEP or any kind of encryption to keep me from watching and recording all your traffic is illegal.

    also you cannot transmit pornography or profanity or music....

    Basically, this will be a very neat thing for Ham radio operators, I have messed with 1.2Mbps data rates at 1.2ghz before.. so this can get cool, but it wil be 100% useless to the large majority of you out there that want to do internet things over it.

  • Important things to remember (Score:5, Insightful)

    by Uhh_Duh ( 125375 ) on Wednesday January 15, 2003 @12:32PM (#5088333) Homepage

    I've been a licensed HAM radio operator for about 11 years now (I got my license back in the days when you had to know morse code)!

    Anyway.. HAM operators aren't just a bunch of radio cowboys out there with expensive high-powered gear. The HAM test itself makes sure that people understand a significant amount of theory before they're allowed to use that gear. In addition, while the laws are very flexible in part 97, they also have some interesting wording. For example, what's the maximum amount of power you're allowed to use in any given band? Answer: "The minimum needed to establish reliable communications". My observations of the HAM community are that these are polite, responsible people and I don't think you need to worry about anyone intentionally causing interfernce to your Wi-Fi network. In situations where HAM's need long-distance high-power signals, they often switch to directional beam antennas so as not to interfere with anyone. If anything, they're going to want to help improve the 802.11b spectrum.

    No reason for anyone to get their panties in a wad. This is a GOOD thing for the WiFi community as you're going to start seeing some very unique and innovative uses for the spectrum -- you're also going to see a very large community with the ear of the FCC fighting to improve WiFi in general.

    • First off, they are using the PROTOCOL and not THE BAND! What I mean is theya re talking about using the 802.11 protocol for communication on the Amateur Bands. This means they will use a Ham Band like 2m, 70cm or maybe the 1.2 GHz band. They are not going to be using the SAME band as WiFi uses. So there's not going to be any problem with them doing this to WiFi. Problems that will happen are 802.11 stuff messing around with 2m voice or other modes (nothing we ain't used to already). Only few words....I doubt 11MB or 72MB even will be possible on these. The bandwidth of the RF signal has to be acceptable to make the frequency usable by multiple networks. An example would be your club wants their own 802.11 network on one freq while the other club wants a freq near you. You have to be separated a bit in order for you to not cross talk. If the bandwidth is too wide, you won't be able to maintain a separation. Also, I think most all WiFi gear uses spread spectrum(ala DSSS) and hams have been experimenting with that for a while. My question is will the hams use spread spectrum also or are they using something different?

  • How about 802.11a? 5650-5925 MHz anyone? (Score:3, Interesting)

    by Skapare ( 16644 ) on Wednesday January 15, 2003 @03:01PM (#5089206) Homepage

    Hams also have 5650-5925 MHz. Of course, RF parts for this portion of the spectrum are more expensive. But antennas are smaller for the same directionality and gain, and the bandwidth is greater. It can open some additional channels, too. Anyone know of any amateur work being done with 802.11a in this area?

  • This is true. It's EASY. There's no more code test for the Communicator license. All you have to do is memorize some really easy stuff. Radio Shack even has a book called: "From 5 watts to 100 watts", that's designed for CB ers! Exams are given every week all over the place. Check out arrl.org for locations and practice tests. Also, there's an iminent FCC ruling allowing hams to use digital encryption for their data. You know you'd like to run an 802.11(b) link with up to 1000 watts, now wouldn't you?

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