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802.11g Approved By IEEE 54 mb/s on 2.4 gigahertz
wavecentral writes "IEEE just approved the 802.11g as the new standard in a vote late Thursday. This enables data transfer rates of up to 54 megabits per sec and works on the 2.4 gigahertz band that 802.11b uses. This in turn makes it compatable and operable between the offical standard." Ewann also writes: "By mid-2002 we should be seeing products based on this technology. Unlike 5 GHz 802.11a, 802.11g is backwards compatible with the huge installed base of 802.11b products. Cool stuff if you want to wirelessly stream video and music in your home. More info on 0211-planet."
It's great that this is backwards compatable, transitioning from one technology is very difficult in itself, going cold turkey where you have to get rid of your current hardware and migrate completely is even worse.
Being able to use your current stuff in conjunction with the new stuff is what will make technologies like this able to improve and expand.
Do you Gentoo!?
Interoperability with 802.11b is nice and all, but at least 802.11a uses reserved frequencies.
This inturn makes it compatable and operable between the offical standard.
Man, my interns only fetch coffee and occasionally do some copying. Where do I get these interns that are able to design wireless networks? Come to think of it, where do I get Clinton-style interns?
Sometimes it's best to just let stupid people be stupid.
Yup. And the neighborhood too. Can you imagine a realtime babysitter network of these things? Or, perhaps a pet watching service...
(Hoping the frequency gives this kind of range)
more info at eetimes
The final proposal calls for two mandatory modulation/access schemes of complementary code keying (CCK) used in 802.11b and the newly allowed orthogonal frequency division multiplexing (OFDM) used in the 5-GHz 802.11a standard. As an option, however, the 802.11g proposal allows for the inclusion of Intersil's original CCK-OFDM scheme, which supports rates of 6 to 54 Mbits/s, and of TI's PBCC-22 (packet binary convolutional coding) method, which supports rates up to 33 Mbits/s.
Three possible coding schemes? This will either drive the price up (to support all three), or lead to incompatibilities when only portions of the spec are implemented. I'd love to find out more... is there some negiotiation in the protocol too see what coding methods are supported?
HIV Crosses Species Barrier... into Muppets
802.11a has very short range, which is why Apple did not implement it in its new AirPort products, but chose to wait out for 802.11g, which will offer the same range and backwards-compatibility. As was mentioned, the products probably won't be available until mid-2002. From an ITWorld article: "The range supported from access point to client in an 11M-bit/sec network is about 300 feet. The shorter, wider radio waves in a 5GHz 802.11a LAN, while offering more capacity, transmit only about 90 feet."
"Reality is just a convenient measure of complexity" -Alvy Ray Smith
Notice that the article is in the Yahoo finance section. If you are an investor, then you would be interested in what stocks would likely be affected by this development.
Sometimes it's best to just let stupid people be stupid.
If anyone can answer any of these questions I'll buy them a beer! the article is decidely fluffy on these details, and a quick google search turned up nothing of value...
1) How does it achieve backwards compatability?
1a) If you throw an 802.11b into an 802.11g network, what impact does it have on performance? i.e. does the 11b drag the network down?
1b) How are broadcast packets sent? (11b or 11g standard?)
2) Is 802.11g more or less resisant to "hostile RF". that 2.4Ghz spectrum is crowded, does 802.11g improve resiliance to interference?
3) How is the range of 802.11g? I understand that the range of 802.11a (the other high speed wireless at 5Ghz) has a much shorter range due largely to the fact that it is at 5Ghz. Does 11g retain the strength of 11b here?
4) What is the security protocol? We all know that WEP in 11b is broken....
If yo uhave the information, please pass it on!
No, they operate on different frequencies, and 802.11g packets are specifically designed to begin the same as 802.11b packets to ensure backwards compatibility. For this reason, many people find 802.11a to be a silly gap-filling solution for fast wireless, especially considering its range.
"Reality is just a convenient measure of complexity" -Alvy Ray Smith
One of my co-workers has been following 802.11g through the standards approval process and he said that 802.11g is designed to "fall back" to using a part of the spectrum reserved specifically for this protocol if the rest of the available frequencies are congested. Although this will help little if there are several wireless networks in a dense area (cf. downtown Chicago), it will help a lot for networks like my home 802.11b setup, which starts dropping packets when somebody fires up the microwave, cordless phone, or X-10 video transmitter. These devices should not interfere with the reserved area of spectrum and thus a moderate level of network performance will be maintained.
It just goes to show that sometimes when the FCC serves the interests of their large corporate customers (who undoubtedly begged for the reserved 802.11g frequencies for obvious business reasons), consumers benefit. Not usually, but sometimes.
~wally
The approved standard is tentative. The group will meet again next year to approve the real standard. This isn't coming to market for some time yet. register article
On the plus side, it will be usable in many countries rather than just North America like 802.11a (which is in a different spectrum) and it should be easier to share the RF section with 802.11b.
On the down side, it is in the same spectrum with 802.11b so you won't be bringing it up in parallel without interference and possible slow downs.
I haven't seen any predicted comparisons for cost, real world bandwidth vs. distance numbers or watts/byte numbers. These will be critical for determining which standard wins acceptance in various markets. No, I'm just kidding. The marketing departments of the manufacturers will choose which we use. I am guessing 'g' because it is later in the alphabet and clearly must be more advanced, but 'a' has that whole letter-grade thing going for it. Could go either way.
so, how long does it usually take for hardware to be made using such standards? And, can I turn my old pentium into a server that uplinks to other computers using linux? I don't like having to buy a new router box each time something fancier comes along.
===> An eye for an eye makes everyone blind - MG
802.11c
802.11d
802.11e
802.11f
802.11h is already under development!
Disclaimer: I really don't know what any of this stuff is, I just searched on google.
The man who trades freedom for security does not deserve nor will he ever receive either. - Benjamin Franklin
What type of range is it possible to get in the unlicensed spectrum? I think there are power output limits that prevent you from setting up high powered antennas to deliver long-range 2.4Ghz wireless Internet access. Also, how will the higher speeds affect the range and reliability of the signal (will it be as tolerant of noise)?
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FWIW, Atheros claims that 802.11a works up to 225 feet and provides more bandwidth than 802.11b at any range. Take it with a grain of salt since Atheros makes 802.11a chips, but it's still worth a read.
It works on the same frequency, so technically the range should be the same.
Perl - $Just @when->$you ${thought} s/yn/tax/ &couldn\'t %get $worse;
The correct answer is "I don't know", but I can tell you how 802.11b maintains compatability with 802.11. In order to maintain compatability between speeds in 802.11, all packet headers are sent at 1Mbps. That way, all clients can understand the basics that each access point is sending. When an AP is involved, the clients only talk to the AP and never to each other. So, as long as the client can tell the AP to send it's own packets at the right speed, everything is good.
I'm pretty sure all the info needed for a client to participate in the collision avoidance algorithms, in contained in most basic of the packet headers (destination address, length (so it knows how long to keep quiet for), etc.) Clients don't need to be able to understand each other, or even the data portion of all the packets. The slower hosts will just ignore the faster packets, but will watch the headers in order to try and avoid collisions.
I know I'm opening some deep wounds in the radio community, BUT,
What about the other users of this spectrum?
Sure people can share radio spectrum between themselves, but there's a big difference between a phone sharing with a microwave sharing with a camera, and a world-wide rollout of a million lil radios sharing with a few private weak-signal radio users.
Yea, it's nice they at least move if they find interference, but what about the "hidden transmitter" effect? (I hear him, he don't hear me.) If I'm listening to an amateur radio satellite, and our new friends start up, would I have to move my antenna away (to keep from overloading the sat), key the transmitter, then move the ant back?
What if I can't send out on the signal cuz it's a listening-only frequency?
Awe heck, it'll work itself out anyways.
Sigh.
-Dan
Could someone tell me how my post was flamebait???? I'm truely baffled
I did some informal testing with a 2.4 GHz cordless phone and some 802.11b wireless gear and didn't see any effect at all on the wireless link when the cordless phone was used around the equipment.
Bleh!
Not from any 802.11b product I have ever encountered. In fact, the existing 802.11b products I have tried are lucky to get anywhere near 90 ft in a real-world environment.
I think whether 802.11a will be better or worse than 802.11b in real life remains to be seen. If its theoretical range is shorter it may actually work better in practice because there is less interference from neighboring users. And the 5GHz band is a lot less busy than the 2.4GHz band.
It would really be nice if IPv6 had mandatory encryption. It just seems to me that encryption should be implememnted above the link layer if you want good security. Link layer encryption is a nice feature, but it's not the optimal solution, IMHO.
If it isn't 3DES or an AES finalist in OCB mode (or CBC/CFB mode with a good Message Authentication Code), I'd be very skeptical. 802.11b manufacturers have shown an inability to provide good initialization vector generators, so counter modes and OFB modes are extremely suspect. ECB mode really doesn't hide message patterns well.
Last I heard, the 802.11e working group was planning on using AES in OCB mode. Unfortunately, OCB mode is patent encumbered. On the plus side, it's really good mathematically. Provable confidentiality and authenticity with very little overhead, assuming the underlying block cipher has certain properties.
They used to think you couldn't get cofidentiality plus authenticity without approximately doubling your processor load. But I've seen the proof to the contrary. It looks pretty convincing. One of the best things that even if someone scews up and uses constsnt IVs, you's still better off than ECB mode.
Copyright Violation:"theft, piracy"::Anti-Trust Violation:"thermonuclear price terrorism"<-Overly dramatic language.
is how they manage to squeeze 54Mbps out of it while still staying within the 2.4GHz ISM regulations?
I have a range type question.
:)
I'm in an apartment building facing North. I have a friend about 10-20 floors below me (so at minimum there are 10-20 floors worth of concrete between us, I forget exactly what floor he's on).
I have another friend in another building that is to the south-east of my building, and he's on the south side and 15 floors lower down. So that means he's probably got 1-2.5 times as much concrete in the way.
What are my odds that *any* of these protocols will connect us? Even if we're using directional antennas? And what are the RF 'radiation' hazzards for the people living between us
(There are no tall buildings at all to the north of our buildings, just 1-2 story residential houses.)