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WiFi Woes With .11g 145

Herby Werby writes "The Register has an article on the incompatibility between .11g and .11b across differing unnamed vendors due to premature roll-outs. The part which really hurts is the suggestion that if there's a .11b participant to your .11g network then either it gets ignored or the network reverts to .11b status. Anyone tried this yet with their new Powermacs?" As the article points out, this is most likely due to the fact that .11g hasn't really even been set as a *standard* yet, so incompatibility is to be expected. I just hope vendors get really good with flash updates.
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WiFi Woes With .11g

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  • I am reading this article while waiting for FedEx to bring me my new 12" Powerbook. I'll check it out when it gets here. It has the Airport "Extreme" card.
    • Re:This is funny... (Score:4, Informative)

      by SeattleDave ( 236077 ) on Monday February 17, 2003 @12:17PM (#5319631)
      My 12PB works great running against my Buffalo Tech WiFi base station and high-gain attenna. How many people really need the faster throughput? 11Mbs seemed fine before the PB arrived with the extreme card and it feels fine now. How many people are buying this stuff to run directly against their DSL or Cable. Let's see... 54Mb/s right up to the goofy router and then, wham, back to 1Mbs/128Kbs down/up.

      The advantage of the new PowerBook like isn't really with the "g" - it's with the great attenna placement. My signal strength has never been better.
      • Uhh... That's the least of it. I have a 15" PB, and an iPod. If I want to move ~5GB of tunes to the iPod from an MP3 share on a Linux box wirelessly, I'll get about 500k/s over 802.11b, but 5Mb/sec over 802.11g.

        Big difference.

        I also NFS mount directories wirelessly, and pull source/data from them. I run X apps from wired servers to a wireless client. That's also much snappier.

        • I hope that is 500 kilobytes/sec rather than 500 kilobits/sec, I assume it is. I get about 6 megabits/sec with 802.11b here. And if you're looking for 5 megabytes/sec with 802.11g you're not even going to come close according to current tests published in eWeek. g barely doubles b's rate with current firmware. Hopefully when things are standardized vendors will start working on performance.
      • by Anonymous Coward
        have you ever tried to transfer files within your LAN at 11Mbs? If you could do it at 54Mbs, do you not see the advantage?

        11Mbs is more than fine for surfing the internet but when you need to transfer large files (1GB+) within you home network, 11Mbs can take up to an hour!

      • "How many people really need the faster throughput?"

        Those wanting increased performance on a home or office wireless network.

      • " How many people are buying this stuff to run directly against their DSL or Cable."

        How many people with a laptop have a switch or a hub right in front of their cable modem or DSL line? Suddenly that 54mbs is useful.
      • I run 802.11b between my build server and my OpenBSD firewall. When I install via ftp after doing a "make release" it would be nice to have additional bandwidth. I also backup over that wireless link to a backup server, in this case I would REALLY like additional bandwidth.
  • by Anonymous Coward on Monday February 17, 2003 @12:08PM (#5319569)
    They became famous for their "v.Everything" modems, which allowed you to basically connect to any other type of modem, even with bad line conditions. Could they produce an 802.11Evertyhing? It could talk to all these incompatible "standards" and sell well to higher end consumers who need guaranteed connectivity.
  • fine print (Score:5, Informative)

    by Bizzarobot ( 442358 ) on Monday February 17, 2003 @12:09PM (#5319580) Homepage
    Little "(2)" [apple.com] at the bottom of the page says:

    (2) Based on IEEE 802.11g draft specification. Data rates greater than 11 Mbps require an AirPort Extreme Base Station, an AirPort Extreme Card, and an AirPort Extreme-ready computer. To achieve maximum speed of 54 Mbps, all users must use AirPort Extreme Cards. Actual speed will vary based on range, connection rate, and other factors
    • To achieve maximum speed of 54 Mbps, all users must use AirPort Extreme Cards

      This is ambiguous; it could mean that to get 54mbs transfers, you'll need two machines that have Extreme cards via an Extreme base station, regardless of any 802.11b products using it, or it could mean that if an 802.11b card is connected, the whole Base Station drops to 11Mbs.

      From the above paragraph alone, it's difficult to say for sure.
      • Re:ambiguous (Score:2, Informative)

        by brianosaurus ( 48471 )
        When my wife's powerbook arrived, we plugged it in and got it on with the extreme basestation. My older powerbook connected through it in mixed mode (or whatever that is). Her old Dell laptop couldn't connect to it. Later we were able to get the dell connected by switching to 802.11b-only mode, but that's lame.

        Anyhow, while it was in b/g mode, her laptop was able to connect and copy files (via AFP) much faster than my powerbook. The "server" was an iMac with 100mbit ethernet connected to the extreme basestation via a switch. I didn't do any throughput testing, but it was noticably faster.

        As for achieving "maxiumum speed of 54Mbps, all users must use Airport Extreme Cards", i think it makes sense. Lets say you have 5 participants in the wireless network (4 clients and a base, or whatever... its not terribly important in this high level example). Lets say one of the clients has an 11b card and the rest have 11g cards. Then lets start transferring lots of data to and from each of them.

        At equilibrium, I would expect that each client will be using about 1/5 of the available spectrum. So the 11b client can get about 1/5 of 11mbps, or 2.2mbps. The others could theoretically split up the remaining spectrum and achieve about 4/5 of 54mbps maximum, or about 41mbps. Even though the 11b client is only sending 2mbps, it takes up 10mbps-worth of spectrum to do it, so the network as a whole can only achieve about 43mbps, not 54.

        Hopefully that makes sense... :)
    • Re:fine print (Score:1, Redundant)

      by quintessent ( 197518 )
      For those not privy to Apple-specific jargon:
      Airport==802.11b
      Airport Extreme==802.11g
    • by matt_maggard ( 320567 ) on Monday February 17, 2003 @04:21PM (#5321165)

      According to this Apple Knowledge Base article [apple.com], the speed of the base station DOES NOT throttle when 11b users are connected.

      It specifically says:

      "Mixing clients on an AirPort Extreme network

      When you mix 802.11b (AirPort) and 802.11g (AirPort Extreme) clients on an AirPort Extreme network, each type of client receives an appropriate data throughput rate. The 802.11g clients continue to receive data at a higher rate than 802.11b clients.'


      The "little 2" is probably there so people don't think that when an 11b user is transfering files to an 11g user that the transfer will zoom along at 54mbs. In this scenerio, all user need to be extreme to get high speeds.

  • by papasui ( 567265 ) on Monday February 17, 2003 @12:10PM (#5319581) Homepage
    thats how long my backorder on the 17" powerbook is. My concern with 802.11g is that it seems extremely distance limited, my dlink 614+ can push 22mbit over 2.4ghz, but it sucks because you need to be right next to the damn thing to get that much throughput. I'd rather have 11mbit and actually be able to get some distance with it.
    • by BWJones ( 18351 ) on Monday February 17, 2003 @12:16PM (#5319628) Homepage Journal
      I'd rather have 11mbit and actually be able to get some distance with it.

      So, the cool thing about "Airport Extreme" is that you can get 54mbit up close and personal, but as range increases and transfer rates decrease, you don't go below 11mbit. It's pretty cool actually as 11mbit is plenty fast for surfing the web and doing database searches, but it is tiresome for data transfers when one is used to the speed and convenience of Firewire. However, 54mbit speeds with Airport Extreme is not to bad for most backups in the under GB category.
    • The performance of the DI 614+ I have is excellent.
      I have no problem with distance problem. I can get a more than decent connection throughout the house. That's roughly more than 40 foot radius.

      By the way, the actual speed of D-Link 614+ and 650+ is 11MBbps with 22Mbps throughput. It is more efficient than the "original" 802.11b

      • >By the way, the actual speed of D-Link 614+ and 650+ is 11MBbps with 22Mbps throughput. It is more efficient than the "original" 802.11b

        Actually it is a real 22Mb/s mode at the PHY level, but since TI [ti.com]
        (who makes the MAC/PHY chip that DLINK uses) got out manuvered in the 802.11 standards wars it had to offer it as a proprietary mode. That's what DLink markets as "2x" mode. If you're in an wireless network with another card that doesn't support "2x" mode it will fall back to 11Mb/s mode.



        Actual throughput isn't near the advertised rate. The 11Mb/s or 22 Mb/s shown on the box is the theoretical throughput at the PHY level. Due to the overhead of the 802.11 standard and vagries of TCP/IP you'll see much less throughput.



        In real world FTP throughput tests done at my office DLink cards averaged 6.2 Mb/s within 115 ft of the AP, while comparable cards ranged from 3.75 Mb/s (SMC) to 4.6 Mb/s (Cisco)

    • it says "By the way, the actual speed of D-Link 614+ and 650+ is 11MBbps with 22Mbps throughput. It is more efficient than the "original" 802.11b

      It should be:
      By the way, the actual maximum transfer speed of D-Link 614+ and 650+ is 11MBbps with maximum of 22Mbps throughput. It is more efficient than the "original" 802.11b
  • by Anonymous Coward on Monday February 17, 2003 @12:11PM (#5319590)
    Erm, this was in the reg seven days ago. Maybe it should be in the "olds for nerds" section instead? (Sorry, couldn't resist)
    • by Anonymous Coward
      Yeah, but as we all know, The Reg is basically a techie tabloid, nothing at the level of /. What the ace editors of /. lose in speed, they make up in quality!
      • Also, the Reg doesn't redo the same story 5 times, each time pretending to be the first. The slashdot way, if I miss a story, there is still a chance I'll get to read it (as new) 1-5 days later. w00t! :)
  • Apple says (Score:5, Informative)

    by Knytefall ( 7348 ) on Monday February 17, 2003 @12:11PM (#5319591)
    "When one or more 802.11b users connect, the wireless network begins to decrease its maximum data rate to accommodate them. When many 802.11b users are active on the wireless network, the overall network data rate begins to approximate 802.11b rates."

    See the "Airport Extreme Technology Overview" at the bottom of this page. [apple.com]
    • graceful fade (Score:1, Redundant)

      by goombah99 ( 560566 )
      If am interpreting this correctly, then this is saying that apples will communicate with extreme cards at the full data rate and the b-cards at the lower data rate. as you add more b-cards naturally the throughtput of the system goes down.

      this makes perfect sense from a bandwidth slice point of view. if each card is getting an equal fraction of bandwidth (or time or whatever) and the b- cards are only exploiting that bandwidth at their normal 11MB/s flux then well yes they are wasting bandwith (but thats becasue they are B-cards).

      the transmitter is still jamming bits as fast as it can, it just cat jam them as fast to the B-cards

      of course a better situation would be if the bandwidth could be shared better so the b-cards got a smaller slice. but I doubt the b-cards would work that way.

    • Bandwidth is shared among the connected users. Sharing is based primarily on the number of users, with a necessary secondary limitation being the limitation of the user's equipment.

      It sounds like a fair way to share a limited resource. Is this a result of a concsious design decision?

    • The .11b packets take longer to send, thus take a bigger timeslice out of the shared resource (the single transceiver). Even though the .11g packets will be of much shorter duration, they will be scattered among the longer .11b packets, making them -seem- to be slower.

      Much like mixing compact cars and tractor-trailers on the expressway.

  • by JWizard ( 542234 ) <abkoffNO@SPAMstudent.math.uwaterloo.ca> on Monday February 17, 2003 @12:11PM (#5319593)
    ...as the register makes it sound ? Obviously different standards will have at least some compatibility issues that need to be resolved, but it seems that the registers depicts it as a huge problem
    • I can't only speak from my limited experience, but we bought the Linksys 802.11g router and were unable to connect to it from any of our 802.11b cards (we've since bought a 'b' access point to hold us over for now).
  • by NivenHuH ( 579871 ) on Monday February 17, 2003 @12:12PM (#5319602) Homepage
    I wasn't able to find any cards out on the market that'll work under Linux.. Most of them use the Broadcom chipset (or a newer rev of the prism chipset) that doesn't work with the existing prism drivers out there.. =/ I tried to toy around with the Linksys "54g" card.. but.. ended up giving up and brought it back.

    *shrug* I figure I'll just wait the 4 months until 802.11g is out of draft and is actually standardized.. People are saying there will be flash updates for the cards.. but.. *shrug* I don't trust word of mouth too much..
    • by Anonymous Coward
      Check out 3com's solutions. I think that they are linux compatible across the board. Everyone else just says "Winblows XP" or Mac OS (9/X). Good luck.
  • Works for me (Score:5, Informative)

    by Anonymous Coward on Monday February 17, 2003 @12:13PM (#5319607)
    I bought a Buffalo 802.11g Air Station for my house that delievered a 4x speed increase over 802.11b. When My wife comes online with her Apple laptop using 802.11b the speed does drop back to 802.11b but since we are hardly ever on at the same time this isn't a problem. I still enjoy the faster speeds and Buffalo has a guarentee that they will upgrade or replace all hardware to meet the standards when they become ratified. Till then i'm enjoying a preview and lovin it...
  • by jptechnical ( 644454 ) on Monday February 17, 2003 @12:13PM (#5319610) Homepage
    I thought 802.11g was made a standard according to this /. [slashdot.org] post.
  • At least until all the standards are sorted out Im going to stick with 802.11b. I know its not exactly blasteringly fast, but manily I just like to surf on my laptop or pda its certainly faster than any internet connection I have access to.
    Added to the most of the sites (not websites real places!) have 11b wireless. Personally until 11g or some other backwards compatible solution proliferates I would rather be compatable than quick.
  • by JungleBoy ( 7578 ) on Monday February 17, 2003 @12:18PM (#5319635)
    I have a Linksys 11g Access Point. There are about 7 11b users (mostly linksys pc cards and usb adapters). I use a powerbook (12inch) with the 11g card, and everything seems to play nice in that network. The powerbook always connects at 54, though the acctual throughput never gets close to that (I test with iperf). The 11b clients don't seem to affect the 11g client.

    • Are you using Nick Sayer's hack on AppleAirPort2.kext or some other 802.11g driver?
      • Are you using Nick Sayer's hack on AppleAirPort2.kext or some other 802.11g driver?

        No, I'm just using the stock setup on the powerbook. Although at home I connect the 11g powerbook to an 11b linksys ap, and only 3 of the channels (9-11) work. But I'm fairly certain that it is an interference issue and not a b/g compatibility issue.
    • Ok, so you're saying I'm safe with having picked up a USB 11b Network Adapter for the kid, and still run the 802.11g Router and the PC Card for my laptop on the same setup ? Have you tried accessing this set from a PDA like the Toshiba e740, or some other WiFi enabled PDA ? Inquiring minds REALLY wanna know... Marcelo
    • Apple and Linksys use the same chipset. Probably the folks with problems are those mixing vendors.

      They didn't get the 'draft' bit...
  • by sczimme ( 603413 ) on Monday February 17, 2003 @12:18PM (#5319639)

    The IEEE Wireless Standards Zone overview is here [ieee.org].

    Recent news from the IEEE re: 802.11 is available here [ieee.org].
  • by timothy ( 36799 ) on Monday February 17, 2003 @12:21PM (#5319656) Journal
    I have a wired + wireless router (one of the many little ones that Walmart / CompUSA / your local Lucky Dragon sell), and it's great, works with very little coaxing.

    However, it also offers throughput on both the wired and unwired sides which is far greater than the bandwidth of my cable modem. For person-to-person communication (IRCing with your tenant in the basement, or even using VoIP if you're into that sort of thing) or moderate file exchanging, 11b is *plenty* until you get pretty far apart.

    How often do you do large file transfers wirelessly so that you'd get a big benefit out of 11g? For some people that answer is going to be "All the time, thank you!" but for most residential wireless users, I think the answer is going to be "Large file transfers ...?"

    Are there really compelling advantages to .11g which would make it worth buying -- for household use, that is -- over a ridiculously cheap 801.11b router? I guess at a frathouse (or a co-op), it would make more sense ...

    timothy
    • Good point. 11b is more than enough for casual surfing and small file transfers. If you ever have a large file transfer (which I do periodically when I bring big files home from work and want to work on them on my big beefy desktop), just walk over to the router (that laptop is portable right?), and plug in a cable. Do your transfer at 100Mbps, then unplug. Easy.
    • IRCing with your tenant in the basement...

      Did anyone else find that pretty amusing?

    • You underestimate the power of pr0n.

    • Are there really compelling advantages to .11g which would make it worth buying -- for household use, that is -- over a ridiculously cheap 801.11b router? I guess at a frathouse (or a co-op), it would make more sense ...



      Depends on your needs. I'm considering an Airport Extreme because of:

      1. USB printer sharing.

      2. External antenna jack for adding an external range extending antenna without modding the case.

      3. My current ABS had the bad caps, and while I hacked new ones in, I still see it as a relatively high risk potential point of failure....

      In short, it depends on your needs and on what you are upgrading from.

      • Hadn't realized that was part of the BSE, thanks for pointing that out.

        Of the wireless routers I've got, one of them (Linksys) has external antenna jacks; the lack of them is one of the only things I dislike about the SMC I'm on right now, though I have never actually attached an external antenna -- I'd still like to be able to if the opportunity comes up ;)

        The BSE is just about the same price as I paid for a messier package of [SMC wireless AP / 3-port switch / DHCP box (with a serial port) + external 56k modem (to attach to the serial port)] However, that 3-port hub has come in very handy; if I had the BSE, I'd have to have an external switch anyhow. A tossup :)

        timothy
  • by Anonymous Coward on Monday February 17, 2003 @12:24PM (#5319683)
    This article has so many errors in it I don't know where to start.

    It says that because of incompatibilities between 11g implementations the IEEE was "forced" to decide between them. WRONG!!! The decision on a final IEEE 11g standard has had the SAME EXACT schedule for the last year per the association's roadmap. And, as the article DOES NOT SAY, the IEEE gave approval to a draft last week, RIGHT ON SCHEDULE. See http://www.80211-planet.com/news/article.php/15847 61 for the complete story. The only sensationalism here is for ignorant reporters being used by vendors who want to inject some controvery into a very technical process.

    The Register really botched this story. Big time.
    • by binaryDigit ( 557647 ) on Monday February 17, 2003 @12:33PM (#5319742)
      Not saying anything about the correctness of the Reg article or of your assesment of it. HOWEVER, you use an example of them claiming the IEEE being "forced" to make a decision, you state that statement is incorrect, and then offer up a couple of examples of how the IEEE was on schedule. What does one have to do with the other? How does the IEEE being on schedule relate to them being "forced" into a choice? Do you have more info to clarify your point?
      • by Anonymous Coward
        Well, let's start with this statement:

        "Now, we hear of incompatibility problems between rival 11g products - discovered in "secret" testing sessions"

        Secret???? Buffalo Tech and a whole slew of corporations are using the same testing labs to ensure compatibility. Both 80211planet and unstrung had information about this. It's a "secret" only to stupid journalists who don't do the minimum gruntwork.

        "How does the IEEE being on schedule relate to them being "forced" into a choice?"

        because it directly says that the IEEE was forced to make a decision on the standard because of vendor pressure, when in fact the IEEE is working directly on schedule on a roadmap set up 14 months ago. There's been absolutely no change in the 11g roadmap, and the IEEE is not being forced into ANYTHING.

  • by puzzled ( 12525 ) on Monday February 17, 2003 @12:24PM (#5319686) Journal
    I realize there is a lot of excitement about the OFDM and increased bandwidth 802.11g is going to bring to the ISM band, but don't hold your breath waiting for your local WISP to roll it in your area.

    http://www.apertonet.com is very active in 802.16, they've got a $2k/channel head end unit, and $1k subscriber units. Its too expensive for resi but it *works* for business - both cost wise and radio wise, which is something I'll never claim about 802.11b. I've got Cisco 802.11b gear in five counties and base on what I've seen from Aperto the only place 802.11b will survive is in very cost sensitive rural areas.

  • by adzoox ( 615327 ) on Monday February 17, 2003 @12:29PM (#5319713) Journal
    I service a large advertising firm - all computers are Macs (Mostly PowerMac G3 Blue/Whites & iMac CRTs 4 G4 Graphites, one Cube, one PowerBook Titanium, one PowerBook G3) - all of these machines have Airport Cards (802.11b) - I purchased an Airport Extreme Base station for this client. All machines worked fine with the 802.11b - just as before with Snow BaseStation 2.0 they had previously.

    This client decided to put a PC on the network along with several networked printers. All networked printers worked fine with current Macs utilizing the "802.11b part" of the Airport Extreme (802.11b/802.11g hybrid)

    The PC, with a Linksys 802.11g card didn't like the network - while it saw the network and Macs saw it, no connection could be made to the internet via AE BaseStation t1 internet.

    I called Linksys, and they said, "At the moment, the Linksys 802.11g (which includes a new implementation of 802.11b) was only compatible with other Linksys equipment". Phone support managed to help me get the 802.11b working. I was transferred to a tech where discussed timeframes and support. I was told that Linksys is actually working with Apple to make a standard since more people initially will buy Airport Extreme. I was told to expect a flash updater for both units by the middle of March.

  • by OS24Ever ( 245667 ) <trekkie@nomorestars.com> on Monday February 17, 2003 @12:35PM (#5319751) Homepage Journal
    I have a Powerbook G4 Ti 550Mhz and an IBM Thinkpad T21.

    I have an airport extreme wireless hub.

    I have an Airport card in the Powermac. It works fine with the Airport Extreme (as one would expect).

    I have an old 'IBM High Rate Wireless LAN' card which as I understand is a 40bit WEP compatible 802.11b card. It works fine.

    So i bought a Linksys 802.11g card for my Thinkpad so I could at least use 128Bit WEP. I plug it in, and it don't work at all. It connects to the base station, but won't get an IP address. If you hard code an IP address it doesn't work either, but it sees the base station.

    Of course I've worked on this for about 20 min, so I'm not finished yet. Not real thrilled with the 'ease of use' crap with Windows 200, wish it'd give more detail other than the pretty graphics.
    • You should read this link [slashdot.org].
    • I had minor teething problems working the other way round. I've been using a Lucent WavePoint II basestation containing an old Lucent bronze card (7Mb/s proprietary, falls back to 2Mb/s standards compliant) at home for the last four years. Yeah 2Mb/s isn't fast, but it's faster than my DSL line, so it's fast enough. It's worked with every 802.11B card I've ever tried.

      Last week I got a new G4 12" Powerbook (very nice, BTW!), with built-in 802.11g. Of course it wouldn't talk to the basestation. To get it to work required re-flashing the basestation to bring it up to more recent spec. After that it worked fine. It's always annoying to have to upgrade firmware, but to be honest I'm really impressed it works at all - I was expecting to have to change the card in the basestation to something a little more recent.

      - Fzz

    • Ah yes. The problem there is that the only wireless networking Windows 200 supports is carrier pigeon. You have to upgrade to a least Windows 1900 to get radio network going. To get 802.11g you have to move to Windows 2000, but I'm not sure if your 18 century old computer can handle that.
  • I've had a Siemens Gigaset phone system (2.4GHz) at home since before wireless really took off. Seeing as there are at least four wireless networks that I know of within 50 feet of where I live, I'm beginning to get quite annoyed with the interference. It's bad enough that I have to share the spectrum with leaky microwave ovens (2.45GHz). Now would all please show some respect and use wireless technology in a different spectrum, such as 802.11a?

    Thank you.
  • by bitty ( 91794 ) on Monday February 17, 2003 @12:45PM (#5319814) Homepage
    This is what happens when you let your marketing department make technical decisions. And don't feed me the "if you don't jump on it early, you'll lose market share" bit. That may be true at first, but if someone buys a product that turns out to be totally incompatible with everything down the road, do you really think they're going to buy or recommend another product from that manufacturer?

    This is going to do nothing but piss a lot of people off and make even more think that .11g sucks ass due to bad word-of-mouth.

  • by The Government ( 88212 ) on Monday February 17, 2003 @12:55PM (#5319898)
    This article doesn't deserve to be promoted on /., and besides is old news anyway.

    The main aim of the article seems to be to try to boost the author's own credibility by making it look as if his previous 802.11g pessimism was prescient. But the author is really trying to stretch the facts to fit his premise; he's not making a useful report.

    He says of the release of pre-standard agreement 802.11g devices: "As predicted, the result is a monumental cockup"

    Monumental cockup? Hardly. These devices work pretty well and manufacturers such as Apple are open about the fact that the standard is still in draft form - and have stated they will release firmware updates to bring their products in line with the final specification when agreed.

    What this article actually gives us is a load of FUD about 802.11g, even quoting a Gartner analyst for a 'techincal'
    explanation!

    It makes you wonder if this guy's got friends in the 802.11a camp...
  • by chriso11 ( 254041 ) on Monday February 17, 2003 @12:55PM (#5319900) Journal
    What is 802.11g? It is a mix of 802.11b and 802.11a.

    802.11b, the commonly seen version, runs at 2.4GHz, just like Bluetooth. Why? Because 2.4GHz is the natural resonance frequency of water, which is the frequency of microwave ovens. So 2.4GHz was left open years ago, because nobody thought it would be any use (a 1KW noise source could completely swamp out the 1nW power of a tranmsitted frequency).

    802.11b uses a digital modulation scheme called CCK, which is basically a fluffed up version of QPSK. 802.11a uses a more advanced modulation format called OFDM, but at 5.2GHz. OFDM is better able to operate in an environment with multiple reflections, but requires a much more complicated modulator/demodulator. But the complexity gets about 5x the data rate in the same bandwidth.

    802.11g was a higher data rate version of 802.11b. Texas Instruments had proposed to use a data format called PBCC to get higher data rates than the CCK used in 802.11b. Intersil proposed to use the OFDM from 802.11a. A standards committee war started, and the end was TI lost. TI wanted PBCC because it was already working on a chipset that would support it, giving TI a great advantage. Of course, Intersil waas probably doing the same thing. When TI lost, it tried to do an end-run around the standard by releasing its chipset anyway. The Dlink plus series and USR 22MB/s Wireless components use the TI chipset.

    • Why is there so much misinformation about the resonant frequency of water? I guess its because everyone assumes that's how microwave ovens works.

      Microwave ovens do not depend on the resonance of water. They depend on absorption of EM energy coming out of the magnetron (water absorbs well at certain frequencies, but DOES NOT resonate). They also depend on that absorption to be "relatively" low so that the mwaves travel through the core of the food object. This does not require resonance (and even rejects resonance as being a candidate for use in cooking). Industrial microwaves can operate in the range of 900MHz as well.
  • Rumor has it that the incompatibility is due to Linsys' use of a Broadcom chipset. Apparently, they (Broadcom) are 'new' to the .11x market and their backwards compat to .11b is a problem.

    Linksys being what they are will probably fix it with firmware then everyone will forget about it.
  • being ratified or anything like that. Regardless of the fact that 802.11g is in Final Draft status and will likely have very few, if any, changes... the issue is entirely whether or not 802.11b vendors completely implemented the 802.11b standard.

    802.11b / 802.11g compatibility relies on implementation of RTS/CTS in the respective stacks. Many 802.11b vendors failed to implement this (for whatever reason).

    Further, the idea that 802.11g access points revert to 802.11b when as little as one 802.11b client is present is a myth! What happens is that when an 802.11g access point is run in compatibility mode, it is forced to use RTS/CTS. The data rate is not slowed down. Rather, it experiences slightly greater overhead as RTS/CTS packets must be used.

    Let us take the time to stop all this FUD now and educate ourselves.
  • My girlfriend's roommate bought the 802.11b/g DSL router/switch combo jobby from the store, and while her one roommate's iBook works great, the other roommate's PC with an orinoco card can't find the network. Maybe a new firmware will fix it, but it really doesn't seem like it was ready.
    • Re:The Linksys AP (Score:3, Informative)

      by craenor ( 623901 )
      If the orinoco card doesn't find the network at all, make sure the advanced wireless settings of the router have "preamble" set to long.

      If that fails, you'll most likely have to change the maximum data transfer rate to 11mbps, thereby hamstringing your 802.11g router.

      Craenor
  • by daveschroeder ( 516195 ) on Monday February 17, 2003 @01:29PM (#5320100)
    In this article [eetimes.com], EE Times looks at some of the same issues.

    However, some of the same misinformation prevails:

    And in an environment of mixed .11b and .11g basestations, Krewell said, clients will automatically default to the lower 11-Mbit/s bandwidth of .11b.

    Not true on two counts.

    First, the only reason that a/b access points don't do this is because they're basically two different access points in one box! If a b/g access point had essentially two access points - one b, and one g - within itself, it wouldn't need to scale back either! Which brings me to...

    Second, g clients don't scale back to 11 when b clients are present. They will get slower, but only because of the way the packets are interspersed. When 802.11b is present on an interface where g is present, everything, including b clients, will slow a little bit; by about a third. But g clients will not slow to 11.

    Also, Apple's equipment has the ability to force b or g only, if needed in a particular installation.

    Ultimately, one Apple design manager said, chip sets will support all three WLAN standards, eliminating any conflicts. Indeed, Intel intends to initially ship .11b chips for its Banias notebook platform, following that up with .11a/b combo chips within three months, and probably add support for .11g by the end of the year, Krewell said.

    Looks to my like it'll be a wash in the end, and I'd rather have g, albeit a draft g, right now (which, if there are any changes, will most certainly be updated to the final g via a firmware update). I can still connect to all b access points, and have increased speed when connected to my g access point (connected via 100mbit ethernet) today.

    Note: this was posted wirelessly over draft 802.11g-Draft6.
  • by Anonymous Coward
    Maybe Broadcom's Jeff Abramowitz won't tell which legacy cards have a problem with 11g access points, but slashdot readers should have no such constraints. I was using an Apple airport with an Orinoco PC24E-H-FC laptop card. A week ago I installed a Linksys WRT54G. The wireless part (with first firmware release) wouldn't talk to the Orinoco card. Installing the January firmware revision solved that problem. Also, the article suggests that using a large number of 11b clients might diminish the results for the 11g users. Setting the new 11g access point to a different channel (frequency) and running both at the same time, with 11g clients using the new channel, should solve that problem. (Assuming one can specify the channel on which the clients are to work - as in Linux).
  • And in other news, 802.11h will replace 802.11a in the futur. 802.11h is still in the 5Ghz band, and will have support for transmission power changes.
  • Toms Hardware Review (Score:3, Informative)

    by OYAHHH ( 322809 ) on Monday February 17, 2003 @01:58PM (#5320302)
    See,

    This article for a review of the Linksys G device:

    Toms Hardware Review [tomshardware.com]

    Lot's of possible headaches listed.

    I bought one anyway, since my SMC Barricade Router broke down the other day. I could have bought an A or a B, but since I try to hang onto my equipment as long as possible I decided to risk it by going with a G machine.

    I don't have any wireless client machines yet, my house has plenty of cat 5 in it already, so I cannot attest to Tom's review.

    BTW, I do not recommend SMC, their device was constantly overheating on me. It's just not acceptable to have to walk all the way to the other end of the house when I want to use the internet (i.e. to turn on/off the stupid Barricade router).

  • by Anonymous Coward
    ...this doesn't increase web surfing speeds at all, because high-speed DSL or cable is actually slower than an 11G card. It does increase your speed on a wireless home network with multiple 11G cards set up in your various boxes.

    But if you don't have a home network, or don't NEED to beat the Joneses in "kewlness", save your money for beer. This is all hype so far, with very little applicability. I don't have a home network, so it would be a 100% waste of money for me. And even if I DID have a home network, why does it have to be cutting edge? Money doesn't grow on trees, you know. I still leave my computer on at night to download stuff, and I don't NEED a home network, since I burn stuff to CD's anyway.

    Bitterman
  • of the v.90 / flex56, 56k modem non-sense. what a disaster that was for consumers.
  • This is almost ... (Score:4, Insightful)

    by craenor ( 623901 ) on Monday February 17, 2003 @03:25PM (#5320849) Homepage
    As bad as the game companies that send out a game still in need of patches. They know there are errors; they know things need fixing; they know it's not a "solid" game yet.

    So what do they do? They ship it...and keep working on it.

    Right now the manufacturers are hiding behind the statement, "this is based on a draft of the 802.11g standard and may differ from the standard when it's published."

    They are putting out a product that will mostly achieve the results people are looking for with 802.11g and hoping they can get the devices into the needed spec with firmware updates when the standard is published.

    On a side note, 802.11g may be a much more viable solution for large businesses. Those companies which require their wireless users to sign in through a DMZ and VPN into the network (thereby not having to worry so much about wireless security problems) will find the added bandwidth of the 802.11g standard very helpful for their wireless users.

    Those of us setting up a home network, well, it's nice to keep up with the Joneses, but you won't see me upgrading my 802.11b wireless network anytime soon.

    Obviously this stuff is based on my opinion, but being a wireless networking specialist at one of the largest computer manufacturers, that opinion is also based on factual observation.

    And no...my company won't be putting out 802.11g equipment until we are much closer to the standard and more of the bugs are worked out between b and g compatibility.

  • The whole problem with shipping several companies' ideas of draft standards is that there's no central certification or testing, as there is with Wi-Fi. Several articles have said that Wi-Fi testing involves a plugfest. Well, there are plugfests, in which lots of manufacturers try interop with lots of devices, but there's also the Wi-Fi certification process with involves lab testing according to a long list of standards.

    When 802.11g is finalized in a last draft soon, then is the time to buy 802.11g gear. I'm testing Linksys and Apple gear now, and although it's fine, there's no great motivation to hop on board until it all works correctly all the time.

    InfoWorld reported this week on problems with speed, WEP compatibility, and cross-manufacturer compatibility. These will be fixed.

    Draft, draft, draft!
    • I completely agree. Historically there has always been a war with who technologies shall be used in implementing the standard. Look at the DVD rewritables, I don't even think they have come to a standard yet. Even with wireless a/b products still work the best when using the same vender for all your parts.

      Wireless-g is a great technology and hopefully will be implemented faster than a/b was. Once they figure out how to standardize it. So for now my wireless network, once again, has to wait.

      • The approach for standardization is there, so we just have to hope that the companies come together.

        I'm guessing we'll see an incredible fast track in July (if ratified then) or the next meeting with the Wi-Fi Alliance producing a ratified-802.11g test suite within months instead of longer.

        Originally, the Wi-Fi Alliance was saying probably 2004 for a way to stamp Wi-Fi interoperability on top of 802.11g, but it seems ike it has to happen sooner.
  • I have a 2x 802.11b access point from D-Link (22mpbs).

    My roommate bought an 802.11g D-Link card, hoping it could run at 22 mbps at home, and faster elsewhere.

    Unfortunately, it only connected at 2 (!) mbps. Nothing we tried could get it to go higher. So, he returned it for a 802.11b 2x card, which works great.

    I don't know if it was just a bad apple, but it was disappointing.
  • Topic Category.. (Score:1, Interesting)

    by bobdole34 ( 444010 )
    I think "Wireless" should be a topic on slashdot.
    There is so much past news and news yet to come on this topic. It makes sense to document and archive it distinctly.
  • I've got a linksys 54g base station, two 54g cards (also linksys) and an Orinoco gold card.

    While I haven't done any serious testing on bandwidth in a mixed environment, I can say that everything appears to play well...at least it does after I flashed the firmware in the base station. (Damn linksys, I didn't pay to be your betatester...I guess that's what that $20 I saved makes me.)

    But seriously, interaction isn't that big a deal in my case. The 11g cards work GREAT on the 11b network at the office, and they work GREAT on the 11g network at home. On the off chance somebody comes over with a 'b' card, everybody STILL has more bandwidth than the cablemodem can feed, and 'g' is STILL a little slow to blow raw video to the fileserver. Other than that, what else requires more bandwidth than 11 mbps can feed?

    BTW, the 11g cards have better signal discrimination...by a bunch.

    Now, if somebody would just port Broadcom drivers to Linux, I wouldn't have to keep using the orinoco card in Linux and the Linksys cards in XP!

    (oh yeah, and a 25 Mb file transfers in about 32 seconds on a 54g network with good signal and no congestion. :P )

    And costs: $149 for the basestion and $69 for each card.

  • Interop between 802.11b cards can be sketchy enough as is.

    I really wish the vendors would concentrate on getting the existing 'standard' working well enough first before going faster. Things like support for real security (TKIP, EAP), and Ad-Hoc

    Even just basic WEP is sketchy on a lot of cards, causing serious throughput issues, or worse, crashing the card.

    Get it together folks!
  • I'm running my PC with a Linksys 802.11g card, a 400-MHz G4 tower with Airport 802.11b, connecting to an Airport Extreme Base Station with no problems. The latest drivers on everything (Linksys card, Airport admin software, Airport card drivers). Windows XP Home, OS X 10.2.4.
  • I just upgraded to 11g with a link sys AP and card. I do see substantial improvement over my 11b (d-link ap and card).
    11g pulls off 2MBps from my server fine. 11b did only 600KBps. The old 11b cards play happy with the new AP. Now I'm just crossing my fingers that the 12"PB that we just got for dad in law works with it. Although I did read somewhere that linksys 11g and Airport Extreme use the same chipsets.
    Strangly, the 11g does seem to improve internet access through my DLS connection. Page loads do seem faster.
    More importantly with 11g I don't see the signal strength drop bellow 50% when I'm in bed :) with 11b I always thought my putty shells where gonna disconnect when reaching for my beer ;)
  • Since nobody knows jack crap how to read English on here. this is DIRECTLY from the Apple Store webpage for the Airport Extreme Base Station.

    5 The AirPort Extreme Base Station defaults to 802.11b compatibility mode when users of AirPort Cards or other Wi-Fi certified 802.11b products join the network. Maximum data rate for AirPort Cards or other Wi-Fi certified 802.11b products is 11Mbps.
  • If you want to get good performance from 11g and simultaneously support older 11b clients, I would strongly advise setting up separate access points on different channels (and not that although you get 11 channels to choose from in the US, they overlap, so there are really only 3 completely independent channels available, 1, 6, and 11).

    The problem is that although 11g products are supposed to interoperate with 11b, they have to slow down to do so. Thus any 11b traffic will seriously limit the effective data rates available for 11g devices. For instance, if you have one 11b device using 5 Mbps of the bandwidth, you won't be able to get more than 10 Mbps from an 11g device.

    I've been involved in 11g product development and have seen this firsthand.

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