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802.11g Slows Down
Moosifer writes "Computerworld reports that in order to step on fewer 802.11b toes, the IEEE has reduced the actual throughput of 802.11g in its latest (and allegedly final) draft. I think I might keep old firmware on my linksys AP and card so that I can at least pretend I have faster gear." It's been moved from 54Mbps all the way down to 10-20Mbps, more than just a slight change.
I don't think this has much to do with politics. Reading the article, it looks like a backwards-compatibility issue such that 802.11g devices don't interfere with 802.11b devices in a co-existing environment.
the blood has stopped pumping, and he's left to decay
the me that you know is now made up of wires
Don't upgrade your firmware. You will be fine as long as you're in a 802.11g only environment. The problem comes when 802.11g devices coexist with 802.11b devices. As it is now, your hardware should be fine.
the blood has stopped pumping, and he's left to decay
the me that you know is now made up of wires
802.11g is not and never has been 54Mps.
The effective throughput of 802.11 is about 22Mps.
54Mps is the effective raw bandwidth.
I have no idea what the new changes will do the speeds of 802.11g, but no one is or has ever gotten 54Mps.
The headline is more than a bit sensationalist; 802.11g still tops out at 54mbps. It's just that in a network with 802.11b equipment, it'll throttle back to 10-20Mbps. It's not quite as bad as you think it is, but you still may want to look at getting a 3rd party hardware solution. If you've got legacy equipment, you may want to consider picking up an 802.11a hub for your high speed equipment. I always thought that apple was silly by offering just 802.11g when all the chipset vendors have said that they're going to be offering combo solutions. Hell, a combo solution, used properly, can provide speeds of over 100Mbps. Someone's just got to create multilink support, much like the old trick of getting 2+ phone lines for dialup and using multilink PPP.
Marxism is the opiate of dumbasses
The rate on the box != the actual throughput you get.
Due to protocol overhead, backwards compatability overhead, physical environment, yada yada yada, you'll see varying throughput.
With current implementations of the draft solution mixed mode performance is *terrible*. 10 Mb/s mixed mode is an improvement. Right now your draft
The standards body hasn't throttled down
Still, by the end of the summer you'll see throughput at 30 Mb/s in pure
In a pure
The compatability
Everybody's going on and on about how it's hardly faster than .11b. Read the freakin article:
.11b is about 5Mbps true throughput. .11g will be twice that in "safe mode" and four times that in pure .11g mode.
"Li estimated that that in mixed 802.11b and 802.11g networks running standard TCP/IP Internet protocols, this will reduce actual throughput to 10Mbit/sec. -- while pure 802.11g networks will have actual data rates of around 20Mbit/sec. Li pointed out that even at these data rates the 802.11g devices still outperform 802.11b devices, which have a raw data rate of 11Mbit/sec. but an actual throughput of about half that speed. "
See that? He's saying
The article would have been much clearer if he had said ".11g is being reduced from 54Mbps raw data rate to X Mbps raw data rate, and from Y Mbps true throughput to 10 or 20Mbps true throughput." Instead he says it's getting reduced from 54Mbps raw data rate to 10 or 20Mbps true throughput. Way to mismatch your units to get the biggest reduction possible.
> I work in wireless at a bug company
How are things at Microsoft?
This phenomenon is one of the signs of the apocalypse.
You were 80% angel, 10% demon. The rest was hard to explain. - Over The Rhine
"Math in a song is good."-Linford
Is this even really news?
At work we've been using 802.11a and 802.11g devices (not to mention 802.11b) since the absolute first days they were each available. All the testing I've ever done was far from impressive and probably close to what they are saying in this article:
802.11b
Advertised Speed: 11 megabit or 1.38 megabytes/sec
Advertised Range: 150 feet
Real-world Speed: 4.5 megabit or 0.55 megabytes/sec
Real-world Range: 100-250 feet depending on interference
802.11a
Advertised Speed: 54 megabit or 6.75 megabytes/sec
Advertised Range: 150 feet
Real-world Speed: 21.5 megabit or 2.7 megabytes/sec
Real-world Range: 50-100 feet (outside of that and the link is so weak the real throughput is worse than 802.11b)
802.11g
Advertised Speed: 54 megabit or 6.75 megabytes/sec
Advertised Range: 150 feet
Real-world Speed: 19.5 megabit or 2.45 megabytes/sec
Real-world Range: 100-200 feet (at 200 feet you can still get better than 802.11b throughput, while 802.11a usually is completely gone at 100 feet unless you are in an open field)
The reality is that they had better start advertising the true speeds and problems of 802.11a/g because a lot of people get disappointed when they compare them to standard 100Base-T wired connections -- to me it's flat-out false advertising. The real-world range of 802.11g is similar to 802.11b and its real-world throughput is consistently 3-5 times faster than 802.11b.
But to say that 802.11a/g are "54 megabit" so people compare them to a 100 megabit ethernet connection is REALLY wrong. It reminds me of the "56k" modems we have in our computers that never connect faster than 40k-45k for most people.
(for the record, our wired 100Base-T network that all these devices are plugged into is very fast -- we have no problem getting 8 to 11.5 megabytes-per-second of throughput)