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The Internet

Email Over High-Frequency Radio in West Africa 192

Posted by michael from the connections dept.
Guillaume Filion writes "LinuxJournal has a fascinating article about Radio Email in West Africa over HF links. 'Deep inside the warm green interior of Guinea, centered in the frontal lobe of West Africa, field personnel in the widely scattered village-towns of Dabola, Kissidougou and Nzerekore now enjoy access to regular internet e-mail, directly from their desktops. Here we have bridged the digital divide, and there isn't a telephone line or satellite dish in sight.' Talk about Wireless Fidelity!"
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Email Over High-Frequency Radio in West Africa More

Email Over High-Frequency Radio in West Africa

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  • Oh No! (Score:2, Funny)

    by Rolo Tomasi ( 538414 )
    More African Spam [slashdot.org]!

  • Reminds me of Packet Radio (Score:4, Informative)

    by ackthpt ( 218170 ) on Wednesday October 16, 2002 @02:19PM (#4463303) Homepage Journal
    Amature radio buffs were into packet radio years ago, I don't know if it's still alive, but some I knew were sending the usual* chit-chat over 2M.

    * "Hi", "How's the weather at your house", "Are you going to Dayton?", "Can I ride with you?"

    • This isn't quite HAM packet radio. Packet radio on HAM frequencies disallows gatewaying content to/from the internet at large.

      • Re:Reminds me of Packet Radio (Score:4, Informative)

        by lucifuge31337 ( 529072 ) <daryl@intros[ ]t.net ['pec' in gap]> on Wednesday October 16, 2002 @02:30PM (#4463395) Homepage
        This is EXACTLY packet radio, without FCC-imposed limitations of what one can or can't do with it. While the article is deatiled and pretty interesting, that obligatory /. "is this news?" is still in order. HF packet radio has been around for a long time.

        If I can find out what freq they're on, all their mail are belong to us.
      • I don't belive they disallow gatewaying to the internet. As I posted earlier, the whole 44.x.x.x class a is delegated to amateur radio operators. Many try to set up tcp/ip networks independant of, but connected to, the internet. Now, when it comes to browsing pr0n from your laptop using your 2 meter gateway at your house, that's a different story. First, things like that aren't allowed on the HAM bands, so you could go buy a license for buisiness bands or something, and second, downloading celebrity nudes at 19.2k probably isn't my idea of a grand time.

        I've used my kenwood th-d7 to irc many a time, but on private channels where i know nobody will be swearing etc.

        Encryption is not allowed, but I must say that I'm guilty of visiting the occasional ssl site, and I'm not totally sure how the FCC feels about that.

        -k6gnu
        • Um, do the rules state such? No SSL? I mean, I'm not really too keen on telnetting to my shell. No competent linux admin is going to want to use anything besides SSH.

          Or does this refer to the rule against hams using private codes or language to communicate with (voice, CW, or whatever). I can't believe the FCC would mandate insecure data communications. Perhaps the rule is a throwback to the days when data security wasn't as big an issue (and there wasn't a public internet to gateway to, etc.)?

          Do you have a URL to the rules, perhaps? Also, knowing what paragraph, etc., in the rules would be handy.

          Arrggh. My ticket just lapsed a few days ago, I just realized (I'm KD4TFF).

          Anyway, I'm wanting to get into packet, and was discussing this very topic with another ham last week.

          • Yes, using SSL or SSH is illegal on the ham bands. The purpose of the "private codes" rule is to ensure that the other rules are being followed. If your transmission is encrypted, how can they know if you are discussing business or downloading obscene material?

            Bottom line is, if you want secure transmissions don't use the amateur radio service. If you really want secure transmissions, don't use wireless at all.

            However, I don't think the FCC will come after you for encrypting a password, like how hotmail uses ssl for login and then drops it afterward. They've always supported the right of private access codes for repeater control, etc.

            I think hams are accustomed to a certain lack of privacy. It's the price we pay for free bandwidth.

            73 de KD7KME

      • Re:Reminds me of Packet Radio (Score:5, Informative)

        by Chanc_Gorkon ( 94133 ) <<moc.liamg> <ta> <nokrog>> on Wednesday October 16, 2002 @03:27PM (#4463824)
        Pretty funny since there are gateways all over the net for this! You just have to be verfied by the operator of the gateway as a ham. Simple phone call, or e-mail would get initial verification. The next would be monitoring your use and making sure you don't use it for what it's not intended for (ie sending porn to other ham friends). This is the act of being a conrtol point operator. You are responsible for everything your station sends as the control point operator. When using a HT you are both the radio operator and control point operator, but sometimes you are not the one talking. Hence repeaters using volunteer control ops that listen to the local repeater via base station or handheld radio. There IS NO FCC Law or restrictiong regarding the use of packet radio except Part 97. Basically you can do whatever you want with it so long as you don't make money(have a pecuniary interest), and you don't send questionable content such as porn, music or other stuff otherwise against Part 97. Transfering MP3's over packet radio would be illegal as MP3 is music. Only way you could do that was if your the space shuttle (only exception to music in part 97 and this is because of the rebroadcasts of shuttle missions. Part 97 does not have the word internet in it and the word network only comes up once and that's in the line stating that a frequency band in the 220 MHz range is to be used for digital packet backbones. Other then that, this is NOT news. I transmitted a packet e-mail cross country before I ever sent a e-mail across country. HF so far has been limited to about 300 baud. I think the most you can do wirelessly using amateur radio is 14.4k(on 2m and maybe 440). The reason for this is because the faster you want to go, the wider your signal gets(hence the term bandwidth..). That's why there's a restriction for 300 baud on HF Frequencies. This may have changed as I don't really have all that much time to keep up on the digital modes. I don't think much has changed though with the excpetion of a couple guys were expermenting with using lasers for voice and possibly data (Would be THz range for RF I think).

        • One correction... (Score:3, Interesting)

          by Andy Dodd ( 701 )
          14.4 is definately not the fastest you can go.

          The GRAPES and WA4DSY modems are (I believe) 56k units, designed for 440 and above. (One of those might be a G3RUH-compatible 9600 design...)

          In Europe, 76k on 440 is common, and the Baycom folks have quite a bit of hardware for this.

          Some guys in Slovenia are doing 1.1 Mbps in the 1.2 GHz band.
          • It's been a long time since I have worked packet. So my info is definitely dated. I have not had a system I could use it with (no free IRQ's). Now that I do, it's too much work to get it going because I have a family. OH well. I guess thats why grey hair runs in the Ham clubs! :)

        • At last check, you COULD send MIDI data over packet radio. This was in one of the ARRL's guidebooks. The MIDI data (and hence MP3) was considered data. I think the example given was one of controlling a musical keyboard remotely.

          Then again, the ARRL has changed their mind about things a few times. I have a 10-year-old "Now You're Talking" that said you could call mayday over a broken down car, since motorists have been killed alongside highways. Newer editions state that you cannot.

          • The ARRL is not the FCC. Only the FCC could make that decision and, to me, the music content of a MP3 or MIDI file could be considered music by the FCC. Although I would tend to side on the ARRL. For a lobbying group (that's what they really are, whether they admit it or not), they ain't so bad. Keep in mind that the ARRL can set operating guidlines for their members but those don't necessarily condone an activity or not. Just because they may say it's ok does not mean that it is, although with the ARRL it generally is ok to follow their guidlines as they tend to the side of the law most of the time. The ARRL changing their mind on whether you can call mayday for a broken down car is just an operating guidline and there's no law regulating it. The ARRL made the suggestion and then changed it due to the fact that words such as BREAK and MAYDAY are code words for when someone is truely in trouble like in danger of loosing their life. Only then should those words be used.

            • Umm... the original ARRL book did indeed call being on the side of the road broken down life threatening, as "motorists have been killed waiting for aid alongside the road." The obvious (idiot) case would be opening your door into traffic. I need to find my pre-no-code-Tech copy again; it's actually quite interesting how quite a few paragraphs throughout the ARRL's "Now You're Talking" have reversed their positions.

              But yes, the FCC is indeed the final authority on this. I have not seen a ruling for music over digital mediums; I just know what the ARRL has said historically -- the new voice codes some HTs have (that could code music digitially) might change things.

              And as an aside, were you at the COARES (Centrol Ohio ARES) meeting this past night? If not, you should join ( www.qsl.net/coares ). Just going by your email address :)

              • Not disagreeing with the book...just saying as you have said...FCC has final say. I also agree with the change to that book too, although I achieved my license with good old hard work and did not need such a book!:) Anyway, no I was not at the COARES meeting. I have no such time for those meetings unfortunately. I have enough things going on with my son, my job, and my church. Maybe when I retire I will be able to do all of the things I have wanted to do with ham radio. Yeah yeah I know it may only be once a month, but ask my fellow CCRA hams how many times I make it to a pizza party (maybe 1 to 2 a year!) let alone getting on the air!
        • You might want to review part 97 - I had someone from the arrl specifically tell me that as long as its not illegal (like its copyrighted) you can transfer music over packet (he used the example of a midi score) since its just data - just don't modulate it over the airwaves :).

          Also - the max keying rate is thus (last I checked)

          160-12 meters 300 bps, 10-6 1200 bps, and 2m up 9600 bps.

          That doesn't mean you can't use some fancy modulation to get more speed - for instance you can use spread spectrum at 70cm and up - like jstar which is 128kbps on 1.2 ghz.
        • Any coding scheme other than straight ASCII (or one or two other represemtations) is also not permitted. Modulation methods are also somewhat restricted, so forget about bandwidth enhancing techniques such as Digital Radio unless you are in the experimental bands.

    • Re:Reminds me of Packet Radio (Score:1, Interesting)

      by Anonymous Coward
      I remember hooking up my Commodore 64 to a ham radio and downloading programs via packet radio. More fun than tape!

  • No longer just a Ham toy.

    Life at 9600baud is more fun anyhow :)

  • In other news... (Score:3, Funny)

    by dubiousmike ( 558126 ) on Wednesday October 16, 2002 @02:19PM (#4463312) Homepage Journal
    West Africans now can order Domino's over the internet.

    Drivers carry less than 20 shiny rocks and buttons on them.

  • Future of networking (Score:5, Interesting)

    by shrikel ( 535309 ) <hlagfarj&gmail,com> on Wednesday October 16, 2002 @02:23PM (#4463333)
    It'll be nice when there are no wires ANYWHERE. The way trends are going now, in a couple of dozen years all communication between people and devices will be wireless.

    If you think about it, much of the last 2 decades' innovations and progress have had the effect (deliberate or not) of making life (at least for those who could afford it) more open and footloose. The company I work for used to have a Chicago address, just because nobody would believe that a large, international, reputable organization would be based in Salt Lake City. Nowadays nobody even thinks about that sort of thing. Even now, with telecommuting technologies, it's not necessary to have all your employees come to the office every day. Maybe in the future, the term "headquarters" will be obsolete, because organizations can be so distributed.

    Okay, it's a little off-topic, but the article makes me think about the steps we're taking, technologically, and where they're leading.

    • There will always be wires. If you think it is bad tripping over a power cable, just try getting your insides cooked by a high power microwave transmitter.
      • Fortunately, I've invented a new invention which I intend to patent. I call it multiple current storage devices. Or "batteries" for short. You plug your device into a wall socket and there are no wires to trip over. I think it's going to be very popular for use with wireless devices.
    • >The company I work for used to have a Chicago address, just because nobody would believe that a large, international, reputable organization would be based in Salt Lake City that's odd...I just am back from Utah and on my way home I saw the headquarters for Ebay in SLC! I also saw a couple of "large international reputable organizations" which can't remember right off the bat that were in SLC...
    • ...all communication between people and devices will be wireless.

      I don't buy that at all. Although it would be nice, it will always be cheaper and more practical to, say, run a wire from your computer to your monitor than to have wireless hubs in each device.

      It is certainly cheaper to go wireless than it used to be, and I think technology will help us get rid of some of the more restrictive and inconvenient wiring, but your prediction sounds a lot like the empty promises of old...like "someday everyone will drive a flying car", or "in the future, everyone will use conveyor belts instead of walking to their destination."

      Technology obviously helps us in many circumstances, but much of the time it's just too expensive to be convenient.

      • it will always be cheaper and more practical to, say, run a wire from your computer to your monitor than to have wireless hubs in each device.

        Will computers still be so modular as they are today? I mean, the iMac has been around for a while and it's not modular. Even though I don't find them very aesthetically pleasing, I saw a single-unit computer the other day while I was looking for a new monitor, which I thought was really cool. It consists of a flat-screen monitor with the computer built into the back of it.

        I think that computers will become less modular than they are now. (Probably not production computers like servers and whatnot, but I refer to user-end models.)

        As for other computer-related things, like keyboards, I think wireless will also become more popular there. You said "it will always be cheaper and more practical" to run wires. Well, with wireless becoming easier and easier, "practicality" might be rated not on price of the unit in question, but on convenience. I, for one, prefer a wireless keyboard and mouse because I hate the wires limiting my mobility.

        The other term you used is "cheaper." A device that uses wireless connections doesn't need a long cord. That's savings right there. And while wireless IS a touch more expensive to make right now, soon the price involved may be low enough that wireless is economically easier. Especially when you need multiple connections to a device. A TV (or other video device) needs several IN and OUT jacks to connect to all the things that people want them to connect to, like Antenna, VCR, DVD-player, etc. What if there was just one transceiver that could communicate both ways with all those devices? And your computer? And your WiFi remote? Forget directly programming your VCR or even your TiVo. You could just do it all through your computer.

        You could run your whole house through your computer, without expensive interconnected wiring for everything. Have your computer turn on all your lights while you're on vacation. And if you get a new device, it'll already link with the rest of everything, so you don't have to run new wires even to a central hub.

        I know, I know, it's what visionaries have been predicting all along, but now we can see a direct path from where we are now to where we could be. (Unlike with flying cars or ubiquitous conveyor belts.) I don't KNOW that this is the path that society will take, but I don't find it too far-fetched.

      • I don't think that its impossible that wireless "hubs" will get cheap enough that they're equivalent in cost and practicality to plain wires.

        We think of wires as being 'free', but they're not. You have to wire up some kind of connector between the board and the "transmission device", be it wires or wireless or a carrier pigeon gate or whatever.

        An especially good possibility is that the hubs will be practically required equipment. If, in this case, the hubs are multi-purpose, the wire-based connection will be an additional cost. Why pay more for wires when you've already bought wireless?

        I guess the case I'm specifically thinking about is computer to keyboard/mouse/monitor/peripherals.

        What wire-based communications can you think of that are not particularly suited to wireless?

        $.02

        -Zipwow

    • Wire is cool (Score:3, Insightful)

      by billstewart ( 78916 )
      Wire is cool. Huh huh.. huh huh... (Sorry, but the pun was just sitting there unused...)


      Wireless is fine for low-speed connections, or medium-speed connections that don't have to go very far, and can either interoperate between multiple users in the same space or else do some non-interference trick like spread spectrum. And it's really nice to have freedom of movement and ability to get some kind of service wherever you are, which means wireless in the most general case (though LANs with DHCP and VPNs are a good start.)

      But fundamentally, wire-like technologies (including fiber as well as copper) are much more practical for high-speed connections, and can fit arbitrarily large capacity in a given area because separate wires don't interfere with each other, unlike multiple sets of radio waves. For high-speed connections over non-short distances, wireless needs line-of-sight, while wires don't need to be in straight lines, can leap under tall buildings at a single bound, wrap around mountains and curved planets, etc. Also, the physics for devices that mess with wires make it easy to put huge bandwidths on a fiber, limited by the cost of the high-tech equipment on the ends (which gets Moore's Law kinds of price/performance effects) - practical bandwidths get into the gigabit range for cheap short-distance equipment ($59 at Fry's) and into the terabit range per fiber for long-distance telco-quality equipment.

      There is some relatively high-speed line-of-site equipment that can fit multiple separate connections in nearly the same space - free-space optics is the most focused, and there are microwave systems that are pretty tight. They can't do long distances, because of weather as well as because of the earth's curvature, but some of them are in the half-gigabit speed range over a few kilometers. They're really nice as a backup for building data feeds - they get rain fade, but they don't get backhoe fade, don't usually need permits to cross highways, and are surprisingly tolerant of earthquakes.

    • It's being said in various ways in response to this, and I agree... wireless will never completely take over for wired solutions. In some places (top of a mountian with my laptop and handheld ham radio, or the article's mention of West Africa) it's better and easier than wires; in others (wireless phones) you can tunnel additional information on a single type of connection...but there are a few reasons wireless isn't going to take over.

      Speed: Generally speed isn't very good on wireless connections. Show me how to get 100megs/sec out of any common wireless connection. This is the wired standard - but you need the bandwidth in wireless connections, and that leads nicely in to my next point:

      Bandwidth: Anything wireless needs bandwidth. Generally faster means more data which means more bandwidth. There is a finite amount of bandwidth. It's pretty much maxed out already (In the US at least; there's lots of military applications, broadcast TV takes a chunk, radio, the ham bands, cell phones, satellite signals, radio astronomy...etc). There's only so much usable spectrum. To put it another way; what happens when your entire city/company/neighborhood/household runs on one connection (t3/t1/cable/dsl respectivly, just for the example)? you oversaturate the avalible bandwidth. Same thing would happen with wireless. If the entire country starts using HF bands for email; your avalible connection speed is going to be shared across thousands of connections...making checking your email a pain in the rear.

      Cost: Look at the cost of a wireless NIC compared to a wired NIC of the same approximate bandwidth capabilites. Do they even make 10meg cat5 NICs anymore? 10/100 seems to be the standard, and even that is cheaper than a wireless card that only can do 11 megs at it's peak.

      There are more but I'm tired of typing...just got back to the room after a long day in the rain. Message me or reply if you have questions or comments. Feedback is welcome!

  • Yes, But.... (Score:5, Funny)

    by LordYUK ( 552359 ) <jeffwright821@noSPAm.gmail.com> on Wednesday October 16, 2002 @02:23PM (#4463334)
    to use this service, you need to send them 2500 which will be reimbursed when they transfer the rest of the money out of their respective repressed country!

  • It's sad really (Score:2, Insightful)

    by DCram ( 459805 )
    I think that this is fantastic and has lots and lots of world applications. But why do I get the sense that what these people really need isnt wireless email to their laptops. How many africans benifit from this? Do they now when hungry email their american counterpart and ask him to describe the BigMac?

    "The International Rescue Committee (IRC) has one of their largest operations in Guinea, providing services and support to a population of up to 200,000 refugees quartered in many camps established throughout the country." I applaud their efforts with refugees and truely do think Guinea is an island of peace in a otherwise bleak sea. But seriously do these 200,000 refugees need google?

    Well enough with this rant.. I do believe that this is a great tech and email is something that I use everyday. Now when on vay-k I will rest assured that i will have email in Guinea!!
    Go ahead and mod me down i know its kinda offtopic but I just needed to say it.

    • African packet radio users will notice faster downloads and less net traffic over the next several years, as half the adults on the continent die of AIDS. [guardian.co.uk]

    • How they would benefit... (Score:5, Insightful)

      by Demon-Xanth ( 100910 ) on Wednesday October 16, 2002 @02:40PM (#4463475)
      A doctor could email a hospital of some symptoms in the field and get a reply of what the illness and proper care for it is. Although the individuals wouldn't get a benefit directly there would be an indirect benefit.

    • Re:It's sad really (Score:5, Interesting)

      by friscolr ( 124774 ) on Wednesday October 16, 2002 @02:58PM (#4463596) Homepage
      I think that this is fantastic and has lots and lots of world applications. But why do I get the sense that what these people really need isnt wireless email to their laptops.

      Decent infrastructure has more benefits than you can imagine. My dad works for the World Food Program [wfp.org] and that org has used many different technologies for communication throughout the world.

      At his last post (Nicaragua) they used Toyota Land Cruisers to get around. Those vehicles were equipped with a multitude of antennas, including some to communicate in the UHF range. For more remote locations they used motorcycles to transport satellite phones where needed. Now he's heading up operations in Angola and i'm not sure what sorts of techs they use there, but i've heard talk of satellite phones and in the capital, Luanda, he uses a cel phone (talking to him from MI, USA is a pain, phone cuts out and is quite laggy).

      While starving sucks, it sucks even more when you can't communicate with anyone that you are hungry. In the past it was necessary to physically visit every single location to see how situations were there. Now, with better communication devices, when something serious happens (hurricane, landslide, refugee influx, etc) it can be communicated much quicker, response times are faster, and more lives can be saved.

    • >I think that this is fantastic and has lots and
      >lots of world applications. But why do I get the
      >sense that what these people really need isnt
      >wireless email to their laptops. How many africans
      >benifit from this? Do they now when hungry email
      >their american counterpart and ask him to describe
      >the BigMac?

      (I really wanted to let this one go, but when I saw the +1 insightful mod I just couldn't help myself)

      What did your post do to help African refugees today?

      Obviously you shouldn't have sent that post because it didn't help African refugees!

    • Re:It's sad really (Score:3, Interesting)

      by dogfart ( 601976 )
      Not true. According to the CIA factbook [cia.gov],

      Guinea possesses major mineral, hydropower, and agricultural resources, yet remains an underdeveloped nation. Let's ignore the mineral part, and note that agriculture is probably to mainstay of most of the population. Internet access, by supporting better agricultural management, will help improve productivity in this area. For example:

      Market and commodity information to assist in export [msu.edu]

      Botany, the science of plants [ou.edu] including pest control, plant breeding, etc.

      Etc. [agricta.org]

      Maybe they don't wire to find out what a Big Mac tastes like, but they may ask about financing export, funds for development projects, scientific information on crop cultivation, etc.

      There is more to the Internet than games and pr0n.

    • Re:It's sad really (Score:2, Insightful)

      by 3Bees ( 568320 )
      But seriously do these 200,000 refugees need google?

      Disclaimer I'm a normal pampared USian and have no first hand or even second hand exposure to this issue.

      I have read reports that this kind of connectivity is a god-send for refugees. The power of email in those circumpstances is related to be irreplacable. The ability to get messages from or to friends, family, or other loved ones is the difference between years of wondering whether some person you care about is alive, and knowing for sure that they are at least breathing and relatively safe (or not, depending on the circumpstances). Since many of these refugees may have family who are working in other countries, it allows them to get messages about state of affairs and to express worries, love, etc. Additionally, the ability to get news from some other source than the camp rumor mill should not be under-estimated.

      Not saying you're wrong, just pointing out that there are many non-trivial uses for technology and that what we take for granted can be a very different experience in contexts that we can not even imagine.

  • Ho hum (Score:2, Interesting)

    by msl521 ( 468252 )
    This isn't really anything new. The first successor to long copper lines in the US were microwave links. Plenty of other developing nations have been using wireless links to reach far flung small villages for a while now. One of the big examples of this has been Chile [freeshell.org].It is especially useful in mountainous areas. In rough terrain it becomes cheaper to put up two expensive microwave towers that it is to pay for the labor of stringing copper or fiber.
  • ... there isn't a telephone line or satellite dish in sight.

    Nuts. As an American, I now have to put Guinea on my "can not visit" list. Thanks, /.

    -DDT

  • And now if they can just get running water, electricity, and roads they'll be set.
    • Water, electricity, and roads would be great.
      But these do not just get installed by gnomes.
      They require a functioning goverment and decent civil institutions.
      These do not survive in countries where power and politics are aligned with tribal sympathies.
      The best way to get around that is to create middle classes who do not care what tribe you are from.
      But middle classes need access to information and markets, and email is one of the best tools for this in West Africa.
      So this kind of infrastructure is not redundant - it is very important and possibly one of the keys to creating better-functioning societies in much of Africa.
  • The radio modems we are using here are speced at an anorexic 2400 baud! And wait, it gets worse. Two-way radio is the classic half-duplex medium of communication; that is, you are either transmitting--push to talk--or receiving, not both at the same time. This, plus the robust error-checking protocols implemented by the modem hardware itself, means the actual link experience is more on the order of 300 baud. Does anyone remember 300 baud? Unless you measure your patience with radio-carbon, your dreams of remote login sessions will be dashed and splattered. As for on-line browsing, chat, video-conferencing and the like, well, best to not even think about it.

    Cool technology, but its still years behind...
    Maybe they've got some of those old BBS programs running. 300 baud + BBS would be great to reminisce to...

    • Re:Speed? (Score:2, Informative)

      by kbielefe ( 606566 )
      I communicate quite happily on my HF radio on PSK31. In case any of you didn't know, the 31 stands for 31 baud, which happens to coincide fairly closely with an average person's typing speed. PSK31 gives a rather robust connection even with my paltry rig and antenna. More importantly, it is extremely narrow band. You can fit at least 10 connections in the space of a normal SSB voice signal. When you set up a wireless LAN in your house, you only have to worry about interfering with other LANs on your street. When you set up a wireless connection on HF, you have to share your bandwidth with the entire planet. On HF, the narrower the better. Why do you need a connection that's 1000 times faster than you can type if all you are doing is sending email?

      73, KD7KME

      • Not just for sending mail. In this case, you could probably also use this for a telnet-type terminal. Depending on the cost (yes, what's the cost) of a typical setup, this could be convenient for sending telnet-type command strings to remote hardware,etc.

  • SailMail (Score:5, Informative)

    by linuxwrangler ( 582055 ) on Wednesday October 16, 2002 @02:28PM (#4463369)
    This setup is very similar to SailMail [sailmail.com] which I have used on several crossings of the Pacific. Yes, it's really slow but that's not a big deal when you are just sending a few paragraphs of text around.

    The last time I sailed across the ocean last July (in the Pacific Cup Race [pacificcup.org]) we used an Iridium phone with the data option. We were able to send back a couple of digital pictures but the phone bill for the week was something like $200. Next time we'll save the pix till we hit land.

  • So does anybody know how secure this likely to be?

  • Careful, folks (Score:2, Informative)

    by PhysicsScholar ( 617526 )
    The range of frequencies over which the electromagnetic spectrum is used in radio transmission is between about 3 kHz and 300 GHz.

    What the article doesn't talk much about is how these waves are actually transmitted. And as science buffs, we're all probably intelligent and curious enough to read a bit about the details of such a feat as this. It may seem complex at first, but it's nothing but physics, which is nothing more than a few algebra rules that most of you learned back in 9th grade.

    The simplest approach to describing radio wave propagation is to solve for the index of refraction h = (m e)1/2, where m is the magnetic permeability (1.25664 x 10-6 H m-1) and e is the dielectric constant.

    The index of refraction, in turn, describes the relationship between the angles of incidence and refraction through Snell's Law.

    To put it simply, all that that mumbo-jumbo really shows is that there's a finite maximum usable frequency (MUF) that will reflect off the ionosphere and allow still higher frequencies to pass through relatively unchanged.

    Bottom line -- email rocks.

  • Its a step up (Score:5, Funny)

    by john82 ( 68332 ) on Wednesday October 16, 2002 @02:29PM (#4463383)
    Before this, they were using carrier pigeon [ietf.org] to transmit email. Just establishing a connnection to the mail server was a bitch.

  • Nigeria has plenty of money floating around (Score:5, Funny)

    by codepunk ( 167897 ) on Wednesday October 16, 2002 @02:39PM (#4463462)
    I would assume that nigeria could easily fund getting the whole country high speed bandwidth. I cannot begin to tell you how many emails I get a day from nigerians that wish to send me millions of dollars just for doing a simple bank transfer.
  • Talk about needing PGP!

  • You thought email was insecure BEFORE..... (Score:5, Informative)

    by FuryG3 ( 113706 ) on Wednesday October 16, 2002 @02:42PM (#4463492)
    ...now anyone in the world can dial in and see your messages.

    Seriously though, hams have been doing this kind of stuff for a while, on various bands. BBSes and email are commonly used (and tied together). There are TCP/IP networks (granted, most of them on bands like 2m which have higher throughput) with internet gateways. As a matter of fact, amateur radio operators have their own Class A (i belive it's 44.x.x.x)

    PSK31 is used on the HF bands and gives you a real matrix feel. You can see the information coming down throughout the band, and click on the stream to see the text moving through it. Here's a screenshot: http://users.skynet.be/on1dht/media/rxpsk_scrn1.gi f

    definitly cool stuff.

    73, k6gnu

    • Re:You thought email was insecure BEFORE..... (Score:4, Interesting)

      by dissy ( 172727 ) on Wednesday October 16, 2002 @03:37PM (#4463903)
      About the 44.0.0.0/8 block, more info can be found by its maintaniers..
      http://hamradio.ucsd.edu/
    • Because it's not the US, they don't have the heavy censorship that US amateur radio users have to put up with (no crypto, no talking about business, no bad language, etc.) It doesn't sound like they're actively using either PGP or IPSEC, but they could, and if they were worried about eavesdroppers, they probably should consider it.

      Since they're using SMTP, a *really* simple thing to do is to enable STARTTLS, which does encryption on SMTP connections if both sides support it, which doesn't have the user-visibility that PGP does and is simpler than IPSEC.

  • Why so slow? What about contention? (Score:4, Insightful)

    by gpinzone ( 531794 ) on Wednesday October 16, 2002 @02:43PM (#4463495) Homepage Journal
    How does this system organize the data streams? What if two people miles apart transmit their message at the same time on the same frequency? How does it handle contention issues? They have an awful lot of bandwidth to transmit so the messages should be pretty "bursty" and fast unless they're downloading entire web pages and such.

  • What? No Mention that the Linux Kernel (Score:4, Interesting)

    by zentec ( 204030 ) <zentec AT gmail DOT com> on Wednesday October 16, 2002 @02:53PM (#4463563)

    supports this already through the ax25 modules?

    This ties amateur ax.25 protocols directly to the Linux kernel. Works great, lasts a long time.

    I suspect the "commercial" modems in use were transmitting in something other than ax.25, probably sitor/amtor/pactor, but it's all about the same at 300 baud.

    The advantage with Linux is that you have to configure one driver for tcp/ip as opposed to dealing with the mgetty and ppp nonsense in the article.

  • Africa has an advantage (Score:4, Interesting)

    by kmonty ( 590999 ) on Wednesday October 16, 2002 @02:56PM (#4463582) Homepage
    This is really the core of the train of thought in Africa. Most of the central African governments are looking at 802.11 type net access as a cheap alternative to putting in expensive infrastructure like telephone lines.

    In South Africa it's even more interesting: there is a definite shove in getting broadband net access working - and working well. In fact, the recent de-monopolising of the Telecoms Company Telkom has finally opened the door for broadband.

    The key advantage, however, is somewhat ironic - in fact, the reason is simply that Africa does not have any decent infrastructure to begin with, this makes it easier to climb in with the leading pack and use leading technology from the start.

    The problem with 802.11 is however that it is unreliable. I've had the opportunity of working with a few wireles net-frastructures using 802.11 to connect a multitude of willing volunteers to various wireless wans and lans. Unfortunately, the best uptime stats we had was around 89%, comparable to the 99.9% uptime we enjoyed with one of Africa's biggest ISPs namely iAfrica.

    African countries have been connecting rather well to the net over the last few years, and doing so beneath the radar for the most part. It however will most likely not become the multi-million dollar industry like it is in the western world, but the key importance of connectivity in remote African cities and Towns is not to establish capitalistic approaches, but rather bring vital services to poverty stricken people, and offer them the opportunities that many dream the Internet still carry.

    Recently I visited a very poor school where the classrooms were the great outdoors and they had one blackboard to share with several teachers. Some students were older than the teachers. The amazing thing was when I saw these kids faces when they saw a pictures of Africa and the rest of the planet we downloaded off the net via Satellite shown onto a makeshift projector screen.

    Stories like this should not surprise people. What surprises me is that people in the western world still think us Africans ride lions and chase each other with spears. Africa is poor, but their is a lot of technological knowledge about. And we have that one advantage...

  • Clover Digital HF (Score:3, Interesting)

    by lenshead ( 215106 ) on Wednesday October 16, 2002 @02:57PM (#4463592)
    I used to dabble in Amateur Radio, mainly 2 meter packet. In those days, about 8 years ago, there were a number of digital HF schemes. About the best of them was Clover -- an AT-compatible board that used its own modulation scheme and protocols.

    One problem with HF is that the ionosphere has a large, time-dependant phase dispersion. It really procludes wide-band schemes unless someone can come up with something very clever.

    The Clover board claimed 500 characters per second, under good band conditions, through a 25 Hz cw filter. At the time, there was no HF scheme that came close.

    I have no idea if Clover still exists -- maybe someone on Slashdot can enlighten us.

  • Good MTA, perhaps, but Open Source? (Score:3, Interesting)

    by AirLace ( 86148 ) on Wednesday October 16, 2002 @03:00PM (#4463611)
    Anyone notice how the author spends the bulk of the article talking about a mail setup using the prorpietary qmail MTA (which has a look-but-don't-touch license [infoave.net] that's in many ways more restrictive than Microsoft's Shared Source) and then goes ahead and praises it as being Open Source in the last paragraph?

    It's funny the LinuxJournal editors didn't pick up on this (the article has already been published in print). I mean, there's nothing wrong with using proprietary software where it's the best option, but calling it Open Source is a bit unfair to both the original author of the software (Dan Bernstein), and the developers of actual Open Source MTAs like postfix, exim and sendmail.
    • Anyone notice how the author spends the bulk of the article talking about a mail setup using the prorpietary qmail MTA (which has a look-but-don't-touch license [infoave.net] that's in many ways more restrictive than Microsoft's Shared Source) and then goes ahead and praises it as being Open Source in the last paragraph?

      qmail is not open source? It is distributed as source code, not binary code. I don't see how that is anything but open source. It is not, however, free software.
  • > Here we have bridged the digital divide

    Psssst! I thought the digital divide mostly concerns those (and the majority) of people who live in these developing countries. Unfortunately the article seems slashdotted - but from that clip it seems like analogy to saying : "Here we have bridged the hunger problem, by taking 42 quality JUST for us". The fact that a few techno geeks can do this really means nothing - even if you describe the surroundings with words " the warm green interior of Guinea". Or do you mean this solution can be easily accessed by those who really are on the other side of the digital divide. (well, have to wait until that article gets back online, but really that clip sounds like example of black humor).

  • For those actually interested in this topic... (Score:5, Informative)

    by DaoudaW ( 533025 ) on Wednesday October 16, 2002 @03:10PM (#4463686)
    Volunteers in Technical Assistance (VITA) have been doing packet radio in the third world for years. Here is their page on communication technology. [vita.org]

    The page also describes their LEO satellite system which is just now coming on line.
  • With internet access becoming more common, it'll only be a matter of time before viruses start to propagate across the airwaves. Never fear though, all you need to do is put a floppy into an machine that isn't online yet [allafrica.com] and the virus will be cured! Honest!

  • any encryption planned? (Score:4, Interesting)

    by HealYourChurchWebSit ( 615198 ) on Wednesday October 16, 2002 @04:16PM (#4464139) Homepage
    So is any encryption planned? There are some sections of West Africa that are still politically volitile. I can see where field workers, such as Doctors Without Borders [google.com] and/or missionaries and/or UN Officials might not want their information intercepted.

    I realize that sending and receiving individual messages should be strongly encrypted, but that still doesn't necessarily obfuscate the sender or the receiver. I mean I'm glad to see such email used as the article says " the radio equipment, providing an essential lifeline for the safety and security of field office and mobile unit personnel" ... but I'd hate to see the same technology triangulated against them.
  • HF can propagate a heck of a lot farther than most VHF or UHF signals. All you have to get is one dirty transmitter, and Lord only knows how many ham, commercial marine, or aircraft HF frequencies it could mess up. Remember the 'Russian Woodpecker?' [sdc.org]

    Has anyone considered the question of interference to other services from this 'service?'

    For that matter, has anyone considered the value of 'net connectivity as opposed to food, medical care, housing, and decent schools? Don't even get me started on the potential for cultural impact.

  • Except it requires rather difficult to obtain ( for the no- techie ) licenses here in the US

    Opening that up to the masses here would help solve that 'last mile' problem,
    among other things.

    ( /me ducks as all the amateurs start throwing rocks for such a suggestion. )
    • Well the no-code-tech license is fairly easy. I think the youngest to obtain it was a 7 year old girl. A friend's son got his at 8. Basic math and a half-way decent memory is all that's required.

      I however took four years of university for mine. (got my BSEE first)

  • The ALOHANET went into operation in 1970. ALOHANET was the first ever packet radio network, operating at 9600 bits per second throughout the state of Hawaii. Aloha is a protocol for satellite and terrestrial radio transmissions. It allows a user to transmit at any time, but risks collisions with other user's messages. "Slotted Aloha" reduces the chance of collisions by dividing the channel into time slots and requiring that the user send only at the beginning of a time slot. Aloha was the basis for Ethernet (a local area network protocol). ALOHAnet was connected to ARPANET in 1972. (Aloha to the Web), (Aloha, pcwebopedia)

    Yep, the name of the Ethernet (as in "transmitting over the aether") protocol is a subtle salute to the pioneering work that went into building the original ALOHANET.
  • They're using PPP to establish a TCP/IP connection over HF. While it's a solution, it's not the best solution - using UUCP and eliminating the overhead of PPP and TCP/IP is a much better, more robust, and higher throughput solution for store-and-forward applications. Been there, done that.

  • When flying across oceans or remote parts of the world (many parts of Asia, Africa, South America, Australia), pilots are not under radar coverage, and conventional VHF radio that they use to talk to air traffic controllers and their own airline don't work, and satellite usage is expensive, so they have developed technology called (Airccraft and Crew Reporting System) and closely related [acarsonline.co.uk] CPDLC [faa.gov] (Controller/Pilot Data Link Communication) for communications between a plane and airline operations or ATC respectively. These are basically text messaging links carried over HF radio. It's not Internet email, but the concept is very much the same.

    These days, an airliner on a transoceanic flight may very well be doing all its communications overwater by HF text messaging, and the pilots will not actually speak to anyone for the entire ocean crossing. While it might seem strange, ACARS and CPDLC communications frees up a lot of frequency congestion for non-routine emergency messages that would otherwise be taken up by traffic such as routine status reports, etc. Think about that next time you cross the pond. :)

  • IBM analogies? (Score:2, Funny)

    by Nobo ( 606465 )
    Yes... But can they use the radios to crush nuts like the IBM Global Uplink Modems?

  • UUCP instead of TCP/IP (Score:3, Interesting)

    by kriston ( 7886 ) on Wednesday October 16, 2002 @08:48PM (#4465968) Homepage Journal
    I was reading this until I got to the description of the PPP link and remembered the days of UUCP over serial lines. Since the modem took care of the error correction they could send much more data more quickly by using straight serial UUCP instead of trying to get a PPP handshake to get TCP/IP working. A UUCP chat script was always faster than PPP in my experience.

    Kris
  • I'm not sure what radio modems they are using. But, it actually sounds a little archaic if you ask me. I mean you have to work with what you have when you're on a budget (or worse ... don't have one). But, it seems that this could be setup a lot better with some equipment donotions. HAMs (amatuer radio operators) are generally relatively generous people. And, all they would need is a couple HF radios since they have the computers already.

    AX.25 is natively supported in Linux, and could easily be leveraged to make this whole thing a lot better. With some donated HF radios, they could have routable RF network up all the time in no time. They might even be able to use APRS instead of AX.25. But, AX.25 is a more proven protocol for this type of thing. See the AX.25 Linux HOWTO [linux.org] for details. Information about the protocol can be found at TAPR's [tapr.org] website. They might even be able to get a little bit more speed, though not much, by using 10 Meter (28 MHz) FM. Though 10M can be probmatic sometimes, so I'm not sure I'd recommend that. 20M (14 MHz) and down are much better frequencies if you want something reliable. A DSP based noise filter would certainly help things in regards to speed, but they cost a bit of money.

    As far as the modem goes... You can use a sound card and a small "control" box. All the box does is operate the PTT (push to talk) circuit. So, you might be able to do with out that if you wire things up just so. But, I have not played with that as of yet. You can also use a Terminal Node Controller (TNC) to get the signal to the radio. Some of the newer TNCs have a DSP filter built in, so that could be an advantage there. But, the best you can hope for on HF is about 2400 bps at half duplex, and 2400 is pushing it. There's just too much noise on Upper/Lower Side Band, and I'm not sure if you would want to use AM (though that might be an option).

    There are a number of sites to check out if anyone is interested in digital commincations over amatuer radio. TAPR [tapr.org] is a very good one, as is RATS [rats.org]. RATS [rats.org] works with a protocol known as ROSE. There is another one called NETROM, but I don't have a link readily available for that. TCP/IP is by far the best for this type of thing though. You can also check out the ARRL's [arrl.org] site, and the FCC's [fcc.gov] amatuer radio [fcc.gov] page, for more information on amatuer radio in general here in the United States. BTW, you don't need to know morse code anymore to get on VHF/UHF. And, to get on HF you only need 5 wpm on the code, which is not all that hard.

    Ok, I admit that last paragraph was a sales pitch. But, amatuer radio seems to be a dying hobby; at least here in the US. So, anything that can be done to increase interest is a good thing. :)

    I'll step down off my soap box now.
  • We're out here in Papua New Guinea (near Australia). We started using Lotus cc:Mail running over the Codan 9002 modems. Then we switched to use a Linux machine as the "router". The "problem" with using PPP is that you can't use Windows on the client side, since there's no way to increase the timeouts, so we're using (C)SLIP. Most of our field workers are less than computer techies, so Linux hasn't been an option on the other end (yet).

    It is excruciatingly slow, so only e-mail is realistically usable.

    We have an ISP here that we helped set up. They've got the radio modems plugged straight into a Cisco router.
  • Dude. I believe this is a hoax. Nice try.
  • Sure, no tel. lines, & satellite dishes, but it needs beaucoup wires, antennae, transmitting and receiving equipment and required paraphanalia. I have worked around packet radio and there are currently very good reasons that it is not a big hit in the US, such as low baud rate, high maintenance, and weird people everywhere. Then again, most of that sounds like us! (Maybe we need a Amateur Engineer Club. AARL is a very successful org.) :{)||

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