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GENRIP for Ultra Low Cost Wireless Deployments 88

Posted by michael from the masochists-wanted dept.
Gregory Perry writes "A South Florida company just released GENRIP, an open source (as in GPL) project for Linux that turns low cost serial line devices (such as 900 Mhz radios) into IP addressable nodes; right now the technology is being used by various robotics groups to replace existing wired tethers on robots with wireless radio links, but the important thing to mention is the ability to use cheap radios to create wireless lan segments without the power and cost requirements associated with 802.11 WLANS."
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GENRIP for Ultra Low Cost Wireless Deployments More

GENRIP for Ultra Low Cost Wireless Deployments

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  • anyone got a... (Score:4, Funny)

    by Havoc'ing ( 618273 ) on Friday November 15, 2002 @01:21PM (#4678109)
    pringles can?

    • Re:anyone got a... (Score:2, Interesting)

      by Havoc'ing ( 618273 )
      not quite the same but cool anyway... http://www.turnpoint.net/wireless/has.html

    • Now as someone who's actually ran into problems with range in a wireless LAN project where the funding was tight, I'm afraid I'm going to have to deflate your joke: building an antenna at home is a bit more complicated than duct taping a piece of stereo wire to a Pringles can. IANAEE so I don't know exactly why, but the piece of wire you use is under some pretty tight specs:

      1. You've got to have the right adapter, which will set you back more than the Pringles, and once you've bought one it probably won't work with any other product.
      2. You need a wire that is shielded, highly conductive, and the right length.
      3. You need to poke the wire into the can at exactly the right point and the right amount in.

      IOW: if you want to make it completely from scratch, first you need an expensive adapter. Then you need a diploma in Electrical Technology. After that, if you're lucky, you can make it work. BION, I never got that farthest node connected...

      • Actually, it is. The hard part for me was finding the special connector I needed to attach to a Cisco/Aironet card, and fighting the traffic to get there (2 construction zones and one school zone). I used a coffee can instead of a Pringles can, but it is the same processs. And it works great - At triple the range of the standard antenna, I ran out of LOS to test with.

        • How much do you know about electronics? If not much: where'd you get your wire from? Like are you saying you just threw everything together and it worked great?

  • not a replacement (Score:4, Informative)

    by nogoodmonkey ( 614350 ) on Friday November 15, 2002 @01:23PM (#4678142)
    They even state that it isnt a replacement for 802.11.

    Unless you're moving relatively small amounts of non-critical information, GENRIP is probably not for you. GENRIP does not even attempt to compete with 802.11 wireless LAN equipment.

    • Re:not a replacement (Score:4, Interesting)

      by Jouster ( 144775 ) <slashdot@angel[ ].com ['faq' in gap]> on Friday November 15, 2002 @01:53PM (#4678391) Homepage Journal
      Yep, with my emphasis added:

      Unless you're moving relatively small amounts of non-critical information, GENRIP is probably not for you.
      GENRIP does not even attempt to compete with 802.11 wireless LAN equipment. That's not what it's for. GENRIP is SLOW! For example, the MHX-910 radios give approximately 120ms round trip ping times, and an actual streaming throughput (using TCP) of about 21K, which is slightly less than your average 28.8K modems. While this is certainly not bad, it's not going to help you if you're looking for fast wireless connectivity.


      Jouster

      • Re:not a replacement (Score:1, Funny)

        by Anonymous Coward
        28.8K huh? good enough for /. (lynx) on some beach in bermuda... after all the pr0n would be right there in meatspace to look at ;-)
    • They even state that it isnt a replacement for 802.11.

      I agree , just too slow for that. But I can imagine many useful with services with low bandwidth, esp. if these slow devices could mesh together to some kind of community network: grassroots SMS, mostly email is fine on slow connections, and even browsing the web with something like lynx or w3m would be doable. But for that these things are way too expensive... Maybe I should reconsider going on with my CB/walkie-talkie network idea...

    • I suppose that bonding several of these network interfaces would be possible. I guess you would have to ensure that the radio signals were set to different frequencies or something as well. Still not enormous quantities of speed, but if it does give you a 20 mile range, still could prove useful.
  • GENRIP doesn't even try to compete with 802.11 wireless networks, because that isn't what it's for. GENRIP is relatively slow (average of 120ms ping? pong! time), and TCP streaming abilities of 21k/second.

    -Kaos
  • I could connect home devices for cheap with this, without having to lay a lot of wires throughout the house.

  • 900 MHz Interference? (Score:3, Informative)

    by JayDiggity ( 70168 ) on Friday November 15, 2002 @01:24PM (#4678152) Homepage
    802.11b runs in the 2.4 GHz band and is interrupted by 2.4 GHz phones, microwaves, and various other devices. This thing runs at 900 MHz, and there are most definitely more 900 MHz phones out there to interrupt this signal. For small groups, maybe this'll work. But unless everyone is going to go back to a corded phone or upgrade their phones to 2.4 GHz, this won't work very well. Cheap, sure, but reliable and effective? Probably not.
  • not use my 900mhz cordless phone while using this.....
    • What happens when you get a call? Even if you don't answer it the phone still sends the ring signal.
      • Yes, but a 2.4 gHz phone has the same risk of disrupting 802.11b, although it's usually seen as a reduction in bandwidth rather than a total blockade, so the user doesn't notice. Again, this is not for mission-critical situations. Although... wireless has NEVER been for mission critical situations, because it is always subject to denial of service from simple RF jamming. If somebody's life depends on it, use a wire.
      • "What happens when you get a call? Even if you don't answer it the phone still sends the ring signal."

        Ah, but I have a quantum phone. If nobody is there to hear it, it both does and does not ring.

  • Give credit where it's due (Score:5, Informative)

    by ekrout ( 139379 ) on Friday November 15, 2002 @01:27PM (#4678181) Journal
    This GENRIP project is based largely in part on the STRIP [stanford.edu] project at Stanford.

    (And no, the STRIP project is not the name of the film crew for Girl Geeks Gone Wild - Winter Vacation In SoCal either. It stands for STarmode Radio IP.)

  • Better not try anything to serious with it (Score:4, Funny)

    by greechneb ( 574646 ) on Friday November 15, 2002 @01:28PM (#4678188) Journal
    I can imagine having some critical item hooked up (for example an O2 tank for grandma) to a computer for monitoring of regulation, and teenager gets on cordless phone to dial her friend, and the 02 tank goes crazy with full force, blowing up grandma like a cartoon balloon. - Not a good thing

  • Man Hours is a Cost too... (Score:5, Insightful)

    by mr_gerbik ( 122036 ) on Friday November 15, 2002 @01:28PM (#4678193)
    Fine, the equipment may be cheap -- and it sounds like you get what you pay for. But what about the cost of man hours it takes to get this up and running. Not to mention the man hours it will take to support some hodge-podge solution to wireless. For all the trouble you will have to go to to get this crappy solution going, you could afford 802.11b that works out of the box on most distros anymore.

    If you want to save some money cutting corners, then build some cheap pringles cantennas or something.

    -gerbik

  • Low cost? (Score:5, Informative)

    by cybermace5 ( 446439 ) <g.ryan@macetech.com> on Friday November 15, 2002 @01:31PM (#4678215) Homepage Journal
    Have any of you priced serial radio modems recently?

    We're talking far, far more expensive than even the more expensive wireless Ethernet cards. Check this out: Arrick's wireless links. [arrick.com]. $650.

    Perhaps there are some modules that, in a manufacturing situation, are pretty cheap. But you're going to have to spend a lot, unless you're interested in developing with TI's transceiver modules [ti.com]. Break out a very tiny soldering iron and a magnifying glass, those flatpacks can get pretty small (this I say right before actually soldering a similar sized chip).

    • Re:Low cost? (Score:2, Informative)

      by dethl ( 626353 )
      It does have something good: better range (300'-3000'). Apple says their Airport Base Station gets 150'
    • > Check this out: Arrick's wireless links. $650.

      That's only because this is a complete solution. You can get transmitter/receiver modules for these kinds of data rates quite cheaply--just pick up a copy of Circuit Cellar and browse the ads. You can find modules for under $20. Of course, the majority are more in the 50MHz range. What makes GENRIP special is that it lets you run IP transparently over these radio modems. Normally when you integrate these radios into a hardware design, you have to implement the entire network protocol from scratch, and most of the time that ends up NOT being IP, believe me.

      • Re:Low cost? (Score:3, Interesting)

        by Hayzeus ( 596826 )
        The units under $20US are generally RF-only. As a rule, you need to implement at the very least some kind of encoding method (manchester or similar) before you can begin to use them (reasonably trivial). These units really aren't "modems". Abacom Technology and Laipac sell some pretty good examples of these units.

        There may be higher end units available for $20, but probably not in single-unit quantities.

        For those really interested, the OCI units that are used at Arrick can often be found on EBAY for cheap (I use a pair of these myself).

      • It still leaves me wondering what makes this so special. What's so difficult about a straight RS-232-style connection? Buffer in, buffer out. Send a packet with an ID number. If someone's talking, wait.
        • For a lot of applications you're correct. This probably becomes useful only if the client application "wants" for whatever reason to use IP. As, for an example, and embedded web server (which begs the question: why an embedded web server?).
    • Aren't ricochet wireless modems serial-communicable radio modems? You can get the older ones for fairly cheap, and the newer ones for probably about $30-40 a piece. Older ones being preferable in areas where Ricochet has been reactivated, due to issues with them deliberately crippling your point-to-point connectivity with the newer modems.
    • The last time I was in Office Depot they were blowing out Cybiko Xtreme units for $50. They network using a 900 MHz Part 15 radio. I didn't get any (too many projects already) and I don't know how easily they can be separated from the logic, or whether they can be reflashed to some other purpose. Anybody tried hacking them?

  • Not necessarily cheaper. (Score:5, Informative)

    by Hayzeus ( 596826 ) on Friday November 15, 2002 @01:49PM (#4678358) Homepage
    It should be borne in mind that a decent 900mhz radio modem is NOT generally cheaper than the equivalent 802.11b device. The real advantage (in mobile robotics) is that radio modems don't require the associated infrastructure to support an 802.11B device (like a PC, for instance) and can thus be indirectly cheaper.

    Having said that, easily microcontroller interfacable 802.11b devices are (at least by rumor) beginning to show up on the market. I have no idea what the cost is tho.

    • I'm more interested in the glut of Motorola's onCore GPS boards that have been showing up for $15-$20. If some wonderful manufacturer ever decided to offer a radio modem board for $20, we could have some interesting combos.

      Th GPS is only 8 channel, but more accurate versions will probably surface soon.
      • At least recently, you could actually get complete GPS units directly from Alltronics (or All Electronics, can't remember which) for something like $15.00 USD. Bought a couple just to have them around. ttl level serial interface. Worth checking into if you just want to goof around.
      • If some wonderful manufacturer ever decided to offer a radio modem board for $20, we could have some interesting combos

        Laipac has something close. They offer spread spectrum voice AND data units for around $30.00USD in single-unit quantities. The catch is that you'll need to provide an encoding scheme for the data (as I mentioned earlier, Manchester is easy to implement), and a simple resistor voltage divider (with most microcontrollers) to get the input level down to the expected 1v = 1, 0v = 0.

        The devices come in 900mhz and 2.4ghz models. I have a couple on order as we speak.

        Geez -- I obviously have a bug up my *ss about this stuff...

        • Sure, Manchester is simple, but you still have to set up a PLL, sample and compare with a flip-flop and get your edge transitions...can be difficult to get tuned right. But then, that's where all the fun is.

  • "Cost requirements" of 802.11 WLANS? (Score:3, Funny)

    by Wakko Warner ( 324 ) on Friday November 15, 2002 @01:51PM (#4678375) Homepage Journal
    Look, if you guys can't afford a few cans of Pringles, I'll chip in a few bucks...

    - A.P.

  • First .ogg Post (Score:1, Funny)

    by Anonymous Coward
    I refuse to purchase this product until it supports the far superior .ogg format.
  • What makes this different from ppp?

  • Linux Has Had an Equivalent (Score:5, Informative)

    by zentec ( 204030 ) <zentec AT gmail DOT com> on Friday November 15, 2002 @01:57PM (#4678432)

    Check your kernel sources. Enable the ax.25 kernel modules and you too can enable tcp/ip over serial devices.

    Add in the supplemential toys which include a niftly "inted"-style super server and you can have it fire applications off on that serial lan, or use kernel routing to route to the Internet.

    Spiffy.

  • Great range with the Microhard wireless modem (Score:4, Informative)

    by Equuleus42 ( 723 ) on Friday November 15, 2002 @02:08PM (#4678534) Homepage
    According to this document [microhardcorp.com], the Microhard MHX-910 has a range 20 miles (line-of-sight) or more. I'm guessing (and hoping) this is omnidirectional. That could prove to be very useful in many applications where the omnidirectional range of 802.11b doesn't cut it!

    Also, did anybody notice that the company's name, "Microhard", is the opposite of "Microsoft"? :^)

  • ultra low cost??? how?? (Score:3, Insightful)

    by Lumpy ( 12016 ) on Friday November 15, 2002 @02:09PM (#4678543) Homepage
    those radios are MORE expensive than 802.11 cards.

    I can get a pair of 802.11 cards for $20.00 each on ebay (ISA type not pcmcia) or even cheaper is the old wavelan cards.. Granted I cant talk to embedded items like a 68hc11 or a Pic with an ISA card, but for what they are trying to do, it's certianly a whole bunch cheaper than buying the 910MHZ devkits they are using..

    when someone says "ultra low cost" I expect it to mean "cheaper than what you can do now."
  • They say that you have to assign unique MAC addresses, which is obviously true, and that they force the high order byte to be zero. But they really ought to mention that you are supposed to set the next-to-the-LSB bit (0x02 hex) in the first byte of the address, in order to designate it as a locally administrated address. The IEEE 802 specs require that you do this if you want to assign your own addresses rather than using an officially assigned block.

    It used to be that the IEEE would only complete OUI blocks (16M addresses). They charge $1650 for that, but now you can buy an "Individual Address Block" of 256 addresses for $550. For locally administrated addresses you don't have to pay anything, but of course you're not guaranteed that they are unique.

    For more info, see the IEEE registration authority [ieee.org] pages.

    There's also a rule that you aren't allowed to use a new OUI until you've used up 90% of your existing allocation. But it's obviously not enforced, since Cisco has over 190 assigned OUIs (not including those of companies they've acquired), and I very much doubt that they've shipped 2.85 billion Ethernet ports.

  • 'Cause you can't have all three.

    I guess that old adage is still true as ever. Still, this seems like good tech for appropriate applications.

    How about authenticated remote access? You carry a small trasmitter (key-fob?) that trasmits an encrypted key over an ultra-low-power encrypted signal (to reduce chances of interception) to a radio receiver at the door which relays it to a server. The server verifies the key and opens the door/gate. All without having to do anything other than approach the door.

  • How is this any better than SLIP or PPP? The document never mentions any advantages.
  • In the example they use the nonrouted (and nonunique) IP addresses in the 192.168.x.x range. Wouldn't this be a problem if you had 2 groups of people doing this independently within radio range of each other?
    How unlikely is this in an urban area?
    • Wouldn't this be a problem if you had 2 groups of people doing this independently within radio range of each other? How unlikely is this in an urban area?

      Too unlikely, I'm afraid. I'd love to chat with someone else setting a network of these babies up. We'd both gain much more than we'd lose by sharing resources.

  • You'll probably see pretty cheap (my guess is $20-$50) Bluetooth serial dongles coming out in 2003. And, of course, you can already get unpackaged Bluetooth modules from Ericsson that effectively have a Bluetooth connector. And you'll probably see more PICs with Bluetooth capabilities. Those are likely to be a more convenient and robust solution than special-purpose 900MHz serial hacks. They will also allow you to talk to the serial devices from any Bluetooth dongle, not just a proprietary one.

    You can, of course, already get Bluetooth USB dongles for around $30. Those are really great little pieces of hardware, and you can stick them on just about any computer that needs to communicate wirelessly.

    I seriously doubt that the boards that GENRIP works with are "ultra low-cost". Their web site doesn't have any prices that I could see, and these kinds of boards tend to be costly.

  • Hello!

    I live in Russia where a) It's illegal to use anything 2.4 GHz without a costly permit; b) It's illegal to transmit anything except the speech on CB band, c) Severity of law is compensated with inactivity of law enforcement, d) Typical income is $100/month and e) All equipment is much more expensive due to import taxes.

    So, I try to design something similar, closing my eyes to all legalities since the law simply cannot be observed. There are 2 projects - 2400/4800 bps CB modem and the 115200 bps TRX working on ChM/FM band (63..108 MHz).

    I try to use the existing AX-25 layer. It's part of Linux kernel, there is WAMPES package that hopefully works under FreeBSD. I have no idea about TCP/IP over AX25 under Windows - I am BSD specialist and don't know Windows at all. Please recommend me some free/opensource or at least shareware TCP/IP over AX25 for Windows, if you can.

    The 115200 project uses TDA7021 as both the RX and TX exciter, PIC16F873 and some circuitry. Duplex mode will require 2 devices per station. The projects are in initial state since they will be required only when the communications authority introduces the metered phone access, that is being planned during more than 20 years, discussed but not introduced. Maybe the government is afraid of people's fury.

    mailto:tango-hotel-oscar-romeo at india-romeo-kilo-dot-romeo-uniform.

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