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802.11b at 22mbps
Radi-0-head writes "According to this article at PCWorld.com, "U.S. Robotics (USR) has boosted the speed of its latest range of wireless LAN products for small businesses to 22 megabits per second, while retaining compatibility with existing 2.4-GHz systems built to the IEEE 802.11b standard..." Sounds to me like a great alternative to 802.11a."
This article refers to USR as a totally stand-alone identity. This is news to me. Did 3Com spin off USR recently? Last I heard, they were a totally absorbed identity, thus no more USR modems or USR Palm Pilots (Irrelevant now). And furthermore, if US Robotics exists again, has Bernard Shifman returned to work there? :)
"Mod, mod, mod...and another troll bites the dust."
More news on the 22mbps USR WiFi can be found here, and the 88W8200 Wireless LAN Baseband Processor information can be found here
geek page at KY speaks
A nearly free 100% speed boost is nice, but I would wait for 802.11g instead, giving 54Mbps in the 2.4GHz band and also being backward compatible with 802.11b.
I'm not an expert, but it seems to me 802.11a is doomed. Is there any reason to prefer it over the upcoming 54Mbps 2.4GHz stuff?
Oh, God no, not proprietary USR hardware that gives superior connection speeds! Not a return to the bad old days!
Shutting down free speech with violence isn't fighting fascism. It IS fascism!
Yessir! 100mW of coffee bean roasting power. A slightly longer wait, but surfing while you wait should be enjoyable. Use a highly directional 26dBi antenna to concentrate that power into a tiny area with an effective power of 25 watts. You might be able to see microscopic bubbles of steam...
This isn't terribly new. Companies have been doing 22Mbps 802.11 for awhile now: Link from 6/2001
Wow!! 22 millibits per second. That means it only takes 45 seconds to transfer a whole bit!
I can't wait until 22Mbps devices come out.
One of these days/I'm going to cut you into little pieces.
So at twice the speed, I can gather enough packets to crack WEP encryption keys in half the time using Airsnort. Seriously, I really want secure security! My office won't move to wireless until there is cheap and proven FIPS-140 compliant security.
11 Mbps to 22 Mbps SOUNDS like a 100% increase, but what is the real speed/range gain? Given an 11 Mbps system with 3 nodes each at 10m from the access point, what is the actual thruput? Is switching to the USR system going to actually DOUBLE that?
Network speeds rank right up there with CRT sizes, CD-ROM spin speeds and tape storage capacity as some of the biggest bullshit numbers in computing.
Learning HOW to think is more important than learning WHAT to think.
Some interesting comparisons of 802.11a, b, g and the various combinations thereof that are kicking around: Clarity & Understanding: The High-speed WLAN standards debate
Is this going to be like the X2 non-standard modem but for the wireless world? If so, then as words taken by the Duke Nukem," Blow it out YER ass!!"
That's the last we need it a half assed proprietary kinda-standard that only works well when you use their equipment.
Reality has a liberal bias
These chips double 802.11b speeds by functioning full duplex. The drawback however, is that this requires category 5 air.
Not all offices and homes fulfill this requirement. Location plays an important role: in the city you'll most likely not be able to communicate full duplex. In suburbs you'll have a fair chance if you're not too close to the city. In rural area's you'll most probably always have full duplex.
You can communicate at 22 Mbps over short distances using category 4 air, but when the peers are more than a few meters apart, category 5 air becomes a must.
Just something you might want to know before you buy these things..
USR does not have a esitmated market release for their new cards (this from a USR sales person).
t io n2x/index.cfm
Some other companies have also started producing the new standard, notably BuffaloTech.
http://www.buffalotech.com/news/prelease/airsta
Any insider information as to when these cards can bought at a local Bestbuy ?
First, the 2.4 GHz has a ton of other devices sharing the same spectrum, from Bluetooth to wireless headphones, to your microwave. 802.11a runs in the 5GHz band instead.
.11b APs will.
Second, according to the last proposals I'd heard of, 802.11g is going to achieve higher bandwidth by taking up more of the spectrum. In other words, it is going to use more channels to simultaneously broadcast data, rather than just being able to shove more data down the same channel. This means your own access points will begin to interfere with each other much sooner than your 802.11a or
In general, it is going to depend on your situation as to which you wish to choose. 802.11g will be great for backwards compatibility, but the news coming out of IEEE seems to indicate that 54Mbps is more like something to shoot for than something they expect to achieve. 802.11a won't have compatibility, and it will also have a shorter range, but it will have higher speeds with less interference.
As you probably know, 802.11a and 802.11b each define a different physical layer. 802.11b radios transmit at 2.4 GHz and send data up to 11 Mbps using direct sequence spread spectrum modulation; whereas, 802.11a radios transmit at 5 GHz and send data up to 54 Mbps using OFDM (Orthogonal Frequency Division Multiplexing).
Sounds to me like a great alternative to 802.11a
Rather than use a hacked non-standard modification of 802.11b, why not use 802.11g? It offers the same transfer speeds as 802.11a, but was designed to be compatible with existing 802.11b networks. So you can upgrade an existing 802.11b network to 802.11g gradually. With 802.11a, you have to rip out your old 802.11b wireless network and replace everything.
lets see, at 22 millibits/sec it would take 1000 seconds to get 22 bits. I don't see how this will be a practical form of networking, it would be faster to read hexidecimal over the phone to the other end.
Spring is here. Don't believe me, look outside!
If you want that just get a Cisco 1200AP, 802.11b now and a few months from now 802.11a. And when 802.11g gets ratified we will have an adapter for that too =) more info can be found here .
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
802.11b
pros:
11Mbps at low cost. Many vendors.
cons:
802.11b operates in 2.4GHz, which collides with among other things, bluetooth, wireless phones, and microwave ovens.
802.11a
pros:
Higher speed at 54 Mbps
Operates in 5 GHZ which is less used
cons:
New radios and antennas required if used to replace existing 802.11b network
802.11g
pros:
Higher speed at 54 Mbps and includes backward compatibility to existing 802.11b equipment
Antennas can be resued if used to replace existing 802.11b network
cons:
Operates in 2.4GHz, which collides with among other things, bluetooth, wireless phones, and microwave ovens.
New radios required because of new chipsets
Sorry, I can't tell you whether a or g is going to replace b, and at what speed existing b users will change to new technology.
11g is really 11a-style OFDM at 2.4 Ghz rather than the 5 Ghz band. There would be two (at least) 11g modes: a compatibility mode whereby OFDM packets and legacy 11b CCK packets coexist, and one which is "pure" OFDM at 2.4 Ghz.
... and these differences are quite small if you have a good 11a radio with a good antenna.
The compatibility mode adds a huge overhead to each transmitted packet. An 11g transmitter in this mode must first complete a legacy 11b RTS/CTS operation on the air which, if successful, is followed by the actual packet. Even if the actual packet were transmitted at nearly infinite bandwidth, the effective bandwidth you'd see on a connection would be quite low - think 10 Mb/s on average. That's not exactly chopped liver and its way better than legacy 11b, but it's definitely not 54 Mb/s.
There are suprisingly large differences between 11a products, even those using the exact same vlsi chips. There are two primary reasons: differences in choice of output power amplifier (or lack thereof) and differences in choice of antenna.
You can deduce some of what's going on by looking
at power and sensitivity ratings in manufacturers product specs. By the way, this also a great way to distinguish between 11b products as well.
Second generation 11a products have much better receiver sensitivity and output power than the first generation versions. And they do transmit through walls... although not concrete or metal or mirrors or some ceramics.
The main reason why 11b can reach farther than 11a in some situations is that 11b can ratchet down to 1 Mb/s whereas 11a is defined for rates from 54 down to 6 Mb/s (11g is identical to 11a in this regard). The difference in SNR and sensitivity needed at a receiver to pick out the 11a or 11g signal accounts for nearly all of the differences in range
Thus, 11g will have the same power, SNR, and receiver sensitivity challenges as 11a in the 5 Ghz band, but will also have a small boost in signal propagation efficiency in the lower band.
Don't get bamboozled by the hype about compatibility with 11b. Compatibility for sharing the channel does not imply that the radio properties of 11g are the same as 11b.
Most vendors are busy bringing out 11a+b base stations and NIC cards. 11g in compatibility mode looks like a nightmare, whereas 11g in "pure" mode looks like 3 more channels of high performance OFDM if you have an 11a radio that can tune to both the 5Ghz and 2.4 Ghz bands. Aside from the higher-power outdoor channels at 5.8, this provides 11 channels for OFDM (8 at 5 Ghz plus 3).
And this means that a group of base stations in an AP-dense environment will certainly be able to find a clear channel.
I didn't say much about the PBCC-based 22 Mb/s products. PBCC is actually a clever design but is likely going to be overshadowed by OFDM at 5 Ghz (11a) and OFDM at 2.4 Ghz (11g variants).
It's funny that you call 802.11a nonstandard when 802.11g is the one that hasn't been finalized. 802.11a/b combo chipsets will arrive before 802.11g chipsets, and at that point 802.11g will be mostly pointless.
You don't have to rip out your 802.11b network to use 802.11a; you can have two sets of base stations and migrate incrementally.
What laptops have 802.11a?
My USR Courier MODEM, now being about 7 years old (my model) was first a V.34 28.8k MODEM, then upgraded to V.34bis 33.6k with a simple firmware download, then X2 56k, then V.90 56k and now it seems, after 7 years, it will be upgradable to V.92 soon.
With an Intel 80186 20MHz (25MHz for US model), TI DSP, flash memory, etc, it is one heavily over engineered beast of a MODEM.
Does'nt surprise me that the company to get extra performance out of a technology, is USR.
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
Umm -- because 802.11g doesn't exist?
It's not something I'd invest in for causual,
enthusiast, or home use, but if you have a business
or operational requirement that can be met by the
product *now*, you should at least evaluate whether
it's worth spending a few bucks on short-term
throwaway hardware (plus the admin tax).
-I like my women like I like my tea: green-
You will *never* get a secure wireless connection
unless you encrypt the traffic using open-source
software on dedicated hardware, end of story.
WEP is perfectly well suited to prevent accidental
eavesdropping, which is all that any vendor-supplied
encrypting driver software (or hardware!) can ever
seriously claim to offer. If you believe otherwise,
you just bought a tanker load of snake oil, my
friend. Closed software/hardware has been proven
by hard experience to be so frequently corrupted
by intentionally inserted weaknesses, that relying
on it for security against snoops and hacks (as
opposed to mere casual scanning) is misguided
at best.
-I like my women like I like my tea: green-
This might be more interesting as a point-to-point
link, however, with a pair of tight yagi unidirectional
antennae, running over open air, you can (one may
suppose) get a VERY fat pipe over a few *miles*,
which would otherwise cost beaucoup de argent, for
OC-12 or dark fiber.
Look, Ma! I made an HDTV MAN for $300!
-I like my women like I like my tea: green-
Saying 802.11a is widespread now is like saying GSM was widespread five years ago - it was in some places, with other countries completely lacking in support.
Blaming GW Bush for the Iraq war is like blaming Ronald McDonald for the poor quality of food.
Well, I am not sold on 802.11b anyway. There was a recent article in InfoWorld that talked about how polluted the 2.4GHz band is. There are things like fusion lighting (so cool!), microwave ovens, cordless phones, not to mention Bluetooth using the same frequency.
Is increasing the range/bandwidth of 802.11b really a good idea? Wouldn't it be better to develop 802.11a (which uses 5.5GHz)?
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