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The Coming Time for 802.11a?
abhikhurana writes "
This article on 80211-planet.com predicts a real boom in the market for 802.11a in the coming year. An excerpt from the article:
In tests in my SOHO LAN, I found that in real world conditions, 802.11a averaged four times faster than 802.11b. In addition, with its 5GHz frequency, 802.11a avoids the interference slow-downs that b must suffer with microwave ovens, high-end wireless phones, and other 802.11b networks.
Also makes an interesting read for knowing about the technologies which maybe driving the wireless bandwagon in the coming years."
bigger faster better more, the endless pursuit "just because we can."
This just sucks... when can i buy it?
I just got may 802.11b installed last week. Curse this need for the latest and greatist!!!
All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
Fresh starters may be more inclined to adopt faster, "cleaner" wireless, but the push will be moving people from 802.11b - having incompatible networks makes buying decisions harder...
Though some will probably opt for both, as many businesses use b, and won't want to spend the money to replace all the cards in all the laptops.
I wonder when Apple will produce 802.11a cards, and if they'll support a & b.
That what was all this school was for... to teach us how to solve our own problems. -- janeowit
This may be slightly off-topic, but it still holds water
How are we going to adopt a technology when MS is deciding for the users what is best.
How about instead of XP deciding to take over for all WLAN third-party software and FORCING you to use an encryption key, let's let the fucking USERS decide what THEY want to do and what software THEY want to use.
Ever since switching to XP (from Win2k) as the host for my WLAN (Dlink DWL-650s in ad-hoc) I have had nothing but poor connectivity.
XP has been reporting that the WLAN is down even if it is working just fine. It won't let me use third-party software to control the WLAN. It forces me to have a network key (it would be different if the range on these cards was over the 25' from the host machine to the furthest reach of the signal).
Just my fucking rant on how MS and their "users are dumb" is really messing w/ME!
How long should I wait to get wireless? I don't want to get trapped in an upgrade loop, like I've been in with computers.
Since '92 I've just been happy to stay 1-2 generations behind to keep the cost down.
Here is a nice comparison of B and A on 80211 planet. Also, a whitepaper for A is available at Proxim Communications. Also, don't forget the FAQ!
My personal feeling about this: The U.S. government should sponsor a 802.11a nationwide network, so we can all have cell phone and data access anywhere, and a provider can 'buy' an area from the government to charge wireless rates for. Kind of like the current system we have in place for land-line phones.
Everyone comes out happy:
the cell phone company has a local monopoly
the customer has access to wireless data and phone everywhere
the government 's pocket gets fatter.
If you don't know what Zoo Blacklisting is, click here.
Anyone care to comment on why this is not prone to problems? Sure Microwaves screw with 802.11b, and cell phones, etc. But who in their right mind thinks that as soon as 802.11a takes off there won't be other devices using that range, like cordless phones, etc... This is going to be a constant problem forever. Since as soon as one device has the right to use a frequency, other devices will be manufactured to use that same frequency...
---
Programming is like sex... Make one mistake and support it the rest of your life.
The truth is about halfway down the article, where they acknowledge that 802.11g is coming down the pike with better range than 802.11a, plus backwards compatibility with 802.11b. Any of us who already have investments in 802.11b are going to be more than a little hesitant to rip out that infrastructure and replace it with another incompatible format - when we can get an even better format, with backwards compatibility, by waiting a few more months.
I don't even buy the argument that homeowners just now getting wireless should get 802.11a equipment: they can't take their wireless cards and use them at public or private 802.11b access points. Why pay extra for something you can only use at home, when you can get something cheaper that works all over the US? It would be like buying a cellular phone that only worked in your neighborhood.
What's your damage, Heather?
..especially when you can use them to their fullest.
Other advantages of the 5 MHz frequency are that the same antenna you use for 2.4 can be used at almost double gain (as long as you're careful), since the wavelength is almost half as long you can use the same antenna. The thoroughput kills 11b by a factor of 5 to 1 at max.
Disadvantages... At 5 MHz, walls are a factor. Objects start to interefere more. So on a campsite, 11a will be amazing. In an office, you'll need repeaters. Hardware costs more right now, on par with what 11b cost at first.. then again, you can get 11b cards right now for under $50.. even Orinocos for under $60.
I used to be someone else. Now I'm someone better.
Real life is underrated.
I think we have reached the 'good enough' point with wireless networking. 802.11b is faster than any internet connection I will have in the forseeable future, and performs perfectly well for the small day to day file transfers over the LAN. It doesn't work for large file transfers, but when I need to do those, I pull out the Wi-Fi card, walk the laptop over to the hub, and plug a spare cable into it's ethernet port.
I won't be upgrading until there is a compelling reason, and I can't see there being one for at least the next 3-5 years.
-josh
It's in dual band devices such as this one from linksys http://www.linksys.com/Products/product.asp?grid=2 2&prid=452
Doesn't "b" come after "a"?
Why does this "a" thing sound newer?
My multimedia machine in my living room runs off 802.11b with a music server in another section of the house. When my 2.4 GHz phone rings, the music pauses nice and automatically (well after the buffer runs out). Its a great feature!
Seriously, webcams, phones, baby monitors all can clobber 802.11b pretty badly. I can't wait for affordable dual mode so I can put the multmedia machine at least in the 5 Ghz range. Home users with lots of tech toys are going to be much happier with 802.11a. 802.11g will do nothing for them.
That is my two cents. Of course, the big variable is when 802.11g recieves finalized specs. 802.11a is already there.
One more question for the grou: I have read a lot (for a Business Analyst) about wireless networking and have yet to see a place which explains the "lettering system" used by the 802.11 products. Why are a, b, and g given those names? Are there 802.11c and d awaiting consideration?
Until the 5 GHz band becomes just as crowded as 2.4?
802.11a is not the wave of the future. It's going to be a nice for those hardcore who absolutely need obscene speed and live in an interference-prone environment.
It has to compete against the HUGE installed base of 11b hardware that is *far cheaper* than 11a and is more than adequate for 90% of the people out there.
I was thinking of upgrading to 11a since I happen to be a power user - But that means that the card I bought would be useless on most networks I might roam to (such as my former college's wireless network). In the end, 11b won out because:
a) I already had some 11b equipment
b) My parents had 11b equipment
c) I have never had problems with 11b interference - Spread spectrum is pretty resistant to CW interference (Microwave ovens - People could run microwaves all they want in my apartment and I wouldn't notice any difference on my network.) and 900 MHz analog is "good enough" for me in the cordless phone arena, which means that the most famous 802.11b interference culprit (2.4 GHz phones) isn't present.
d) 11b hardware was a helluva lot cheaper than 11a hardware.
retrorocket.o not found, launch anyway?
A 10 mbit 802.11a can cost as much as a gigabit NIC, which isn't too favourable if you're not going to do much roaming. The fact that you have to buy several Wi-Fi cards to get a wireless network together makes the proposition daunting for homes and small businesses. It doesn't have to be fast (or even secure, that's what ipsec is for), but for the technology to become truly ubiquitous, it needs to be priced at commodity levels, say around £10 to £15.
Personally I'm hedging my bets on systems that offload most of the processing to the host CPU like the stuff Microsoft is working on. It allows not only for cheaper hardware, but also gives more flexibility and upgradability (care to upgrade your Wifi setup to 100mbit with a software update?) The only thing that could potentially go wrong with this technology is if Microsoft tries to abuse its position and fails to release open specs for the hardware or releases proprietary (or no) drivers for non-Windows operating systems. However, given their commitment to FreeBSD it's quite possible that they'll go ahead and release some BSD-licensed reference drivers for FreeBSD which can be ported to other architectures.
I belive that you cant legally run 802.11a in the UK or europe
intel had to get a licence for London Fashion Week where they did video streaming of differant shows
not sure about china or taiwan anyone know
regards
John Jones
If I was sitting normal in a chair and using the computer, no problems.
I see this a a bigger push from 802.11b, as the 11a components will now demand the high price, 11b components will drop even more.... eeeexcellent Smithers.
This is not the sig line you are looking for... -- Old Jedi Sig Line Trick
I was a beta tester for a 802.11a product in early 2001. I was attending school at RPI and our test product did not reach through the dorm walls. I couldn't, on high power, reach to the dorm next door. However, with the same company's 802.11b system, it would go all the way around the building. The issue is that 5ghz drops off faster than the 2.4ghz equipment.
The real world:
That said, a small office or home that can be covered by a single unit should work acceptably. I would wait for 802.11g before installing a large number of units based on 802.11a, especially for any core business use.
It's in dual band devices such as this one from linksys
The device you point out is an access point, not a card. Buying a combo 802.11a/b access point means you have to have 802.11a access *cards*, or else your money on the a/b access point was wasted - and you should have just gotten an 802.11b access point. But if you have 802.11a cards, then you can't use them at the public/private access points away from your house/job - like at coffee shops all over the place these days. So these combo access points really don't help much.
What's your damage, Heather?
I'm just wondering...does 802.11a not operate in the 5.8 GHz range? I know there are three chunks of the 5 GHz area, so is 802.11a going to work in the low and middle bands only (5.15 -5.35)?
I ask because I know VTech (and so other manufacturers, probably) are selling 5.8 phones now, which I assume are operating in the high band.
Fortran programmer...oh yeah. Array math for life!
They do, linksys just put out the WAP51AB. To bad it goes for $300 though. Just came out so the price should drop
does anyone actually know of a PCMCIA card that does both Bluetooth and 802.11b ?
that would make alot of people Very happy
regards
john jones
p.s. bluetooth phone dialup when your not in the office and 802.11b for when you are
I own two D-Link DWL-650 cards. The range was never all that great (even in Linux). I assumed it was the fact that I was communicating card-to-card.
Things became much better when I started using a proper AP.
Later on, I needed a WLAN card for my desktop. After a BAD runin with a D-Link DWL-520 that I promptly returned, I tried a Orinoco and PCI carrier. The PCI adapter didn't work to well on my desktop. (Fine under Linux, useless in Windows) I returned the PCI adapter, but because the Orinoco had seemed to give slightly better performance and was supported by Netstumbler, I kept it.
A few weeks later I pulled out the D-Link once again for comparison - At that point I realized just how bad it was.
Side-by-side in the same place, the Orinoco blew away the D-Link. Orinoco reports a "good" signal strength upstairs. The D-Link barely gets signal. Downstairs, the D-Link reports low signal strength IN THE SAME ROOM AS THE AP! The Orinoco is pegged at full strength in this case.
I'm sticking with Orinocos from now on...
retrorocket.o not found, launch anyway?
I'm sitting here using my computer at work over Remote Desktop (yes, stuck using Windows crap, but as Windows goes, this remote desktop stuff is pretty trick). Wireless network is pretty much pegged between this and local stuff. I'm showing solid green (excellent signal), and I'm sitting here on my DSSS 2.4ghz cordless phone.
Now maybe if there were other phones or something in the area it'd be a problem, but I'm just not seeing it.
So as the 'new wave' of 5 GHz devices come out, the next phones will again mess with wireless. You get rid of the microwave, but not phone. Personally, I have not experienced problems with 802.11b and interference.
Range will, however, be hurt. Wireless becomes pointless as the range diminishes. Range matters in some ways more than excessive bandwidth. Beyond 11 Megabit, it certainly doesn't matter much. For 95% of the applications out there, the extra bandwidth is unnecessary. I am able to stream extremely high quality video content through that to a handful of users on a single access point. Accessing things through network shares are still a pain in the ass at 100 megabit, so the added pain of 11 megabit most of the time isn't enough to make the sacrifice. As they say, 802.11g looks more promising, but in any event I can for about a hundred bucks set up a wireless system and client with 802.11b that suites all my needs. Why bother?
XML is like violence. If it doesn't solve the problem, use more.
Distance affects usability, of course - if the thing can't talk from the living room to the bedroom, that's a problem. But speed isn't enough to justify the extra cost for most home users.
Business is a different matter - there you often have enough machines sharing a server in the same building that total bandwidth matters.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
If your microwave is interfering with ANY 2.4Ghz product then REPLACE IT ASAP. A microwave in good operating condition should not leak any 2.4Ghz radiation as the entire chamber should be properly sealed and the screen on the front of the microwave should keep the radiation in. Some people freak about cell phones and wlan devices, but the max power output of an 802.11b radio is 100mw for a client card, while a microwave over has radiated power in the hundreds of watts.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
But some definately are. I have a coworker that has an 802.11b network and a 2.4 GHz phone - His network gets *clobbered* when he uses his phone.
retrorocket.o not found, launch anyway?
I don't see this happening with 802.11a. The range for a is MUCH shorter than the range for b, and even b is rather short. There would need to be some way to put out a much stronger signal with a to make this effective. Simply put, I don't see a government nationwide wireless network happening for another year or two. The technology still is not there yet. Of course, the rate of change is getting faster by the month now, so my prediction may be more out of date than 640k in 6 months, but time will tell.
"I may be quite wrong." - Socrates
about a month ago (D-Link DWL-6000AP). We have 802.11b in the other building and I decided to try 802.11a down here to see how they compared.
.11b and hard barriers (concrete walls, walls with a lot of steel, etc.) seem to attenuate the signal much more quickly. I don't get nearly the range with 802.11a here as I did a couple of years ago when we tested 802.11b here (before moving it to the executive building.) Speed drops off much more quickly, too: I get about 40-50 feet here in the office at full speed and then it drops off very quickly to 802.11b speeds beyond that, before finally quitting altogether at about 90 feet.
.g comes along: .a seems like a -very- interim technology with few advantages and some serious faults.
802.11a has a noticably shorter range than does
If it were me, I'd stay with 802.11b until
On the plus side, all of our Thinkpad notebooks with built-in 802.11b work effortlessly with the D-Link access point. I've got three systems (two notebooks, one desktop) with the 802.11a cards in them and half a dozen Thinkpads with 802.11b either built in or with cards and it all works very well.
There are companies out there who use this 5 ghz unlicensed band to do reliable 50+ mile shots using 6-8 foot dishes. Radio stations also use it for digital studio to transmitter links.
Andrew makes a line of dishes for this band that are very popular.
China, Europe etc all have issues with Radar interference in the 5Ghz band. Only when the military people in each of the various markets sign on will there be widespread 802.11a penetration. The technology is there, no question about it, it's the regulatory issue that is the holdup. Lobby your govt in the respective countries to get it approved. Until then, volume manufacturing will always favor 802.11b/g for now.
802.11a devices are not powerful and have difficulty with any objects that would obstruct the sight. to get near maximum speed, you have to sit in line of sight around 10-15 meters from the
device. Bandwidth deteriorates quicky as you move behind walls.
That was my experience with 802.11a. There should be intermediate solution @ 3.2 ghz or around there, so people can get better range out of their devices. 802.11a, is to be used as replacement of inhouse networks, nothing more.
I guess this is great for cafes and alike due to reduced range, they don't have to step on each
ones toes...
2c,
p.
Very loosely speaking, I see the triad of 802.11, 802.11b, and 802.11a as being like the triad of Ethernet, FastEthernet, and GigabitEthernet.
There was once a time when everyone had Ethernet, and all was good, if a tad bit slow.
When FastEthernet came out, there was some initial hand wringing, but pretty much everyone has moved to FastEthernet and declared it The Standard. Since it was the prevailiing technology at the time that computers with integrated networking were starting to come out in droves, FastEthernet has achieved critical mass.
Now, Gigabit Ethernet is out, but no average home user will ever see it in his computer. He's not likely going to need that high performance, and is certainly not willing to pay for it. It's a specialty application product.
Similarly, the older 802.11 wireless cards (2 MBit) was a good thing at the time they came out; but they were still a bit too slow.
When 802.11b came out, the performance reached a good level for the most common wireless use. And the price is pretty darned good. And since most laptops with integrated wireless come with 802.11b, it is achieving (has achieved?) critical mass. (Or is that critical mess?)
Although 802.11a is now available, they are too expensive and have not yet achieved the interoperability track record of 802.11b. And, besides, if you have a portable wireless network application, you probably don't need the higher speed. Really now, when was the last time you compiled your kernel over wireless? Or streamed video from a server to watch it on your laptop while you're seated at your comfy couch?
The world got along fine with Plain Old Telephone Service for a 100 years.
Now, wired FastEthernet, and wireless 802.11b is the "pretty good and cheap" solution for the masses.
This seems to be the conventional wisdom, but the technical specs indicate that at a given range a is faster, and that they both drop off at roughly the same range.
Can anyone point out any docs that show why a should have a shorter range in practice? Is it just because 5GHz is not as effective at penetrating barriers?
-Peter
Exactly.
Let's see, would I rather dl Win2k SP3 from microsoft 3 times, or 1 time and copy it to the other two computers at 100Mbps? Tough question.
Bandwidth to the internet is not always a bottleneck.
Keep in mind that in 802.11b the farther out you are, and the more interference there is, the lower you rate is. It will switch from 11, to 5.5 to 2, and then 1 as the signal gets weaker or more corrupted. The same is true for 802.11A, accept [sic] the range is way smaller, so you will get a reduced rate at ranges where 802.11b is still running at full rate.
But reduced rate 802.11a is still twice as fast as full rate 802.11b.
That is the reason I bought 802.11b instead of 802.11a:
I need the extra bandwidth because I use the wireless to stream video (divx) on a daily basis. 11 Mbps is barely adequate and often causes jerkiness in high quality video. So I did some reasearch on 802.11a to find the one best supported by Linux. The result? There is *no* support for any 802.11a cards as far as I could tell. So I didn't buy any.
Some of these companies need to figure out that early adopters are also people likely to use Linux...
Sure, you're weird (:-) So are many of my friends, like Hugh, whose house is "mainly insulated with copper wire". But when you're talking about mass-market adoption of a product, that's not who buys most of the millions of units - it's the people who probably have multiple computers and don't want to wire their house with Cat5E and fiber, but most of the computing horsepower is in the house is the kids' game machines and maybe the adult's work laptop. Business usability is a different matter (that's why the word "home" is in the subject line :-), but businesses probably won't be really mass adopters until the security issues are fixed. 802.11a prices have started to come down enough that in a new business installation it's almost certainly worthwhile, but for mass-market home use the main reason for it is better coverage (or sharing with your neighbors.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Before modding this down as a troll, please read the whole thing:
802.11a is horrible. The testing I've done for my company indicates that the highest actual throughput you'll get with an access point is 8Mb. The highest you'll get ad-hoc is 18 (which is actually pretty good).
The problem is that kind of throughput is only possible when the system is right next to the AP or when the two systems are practically touching. If you walk a few meters and have line-of-site, you'll be able to get +10Mb throughput with the two adapters in ad-hoc, but if you go around a corner it drops off radically.
Now, why does 802.11a have such a problem with corners? Because the higher frequency transmissions will not bounce as well. Rather than diffracting like 2.4GHz transmissions do (diffraction is the bending of a wave around an obstruction), the radio waves bounce, diffuse, etc. Basically, the signal breaks up.
802.11b, though (and 802.11g) will route around obstructions better because of the lower frequency. The lower the frequency, the more diffractive the signal. I predict 802.11a will be passed over for 802.11g. Especially because 802.11g is backwards compatible. The real panacea will be cards that work with 802.11a/b/g. They'll have to have two different antennas, but they'll be kick-ass.
XP seems to be (oddly) missing support for Prism2 (i.e. DWL-650, SMC, Linksys, etc.) cards - My Prism2 wasn't detected by XP.
But if you want to use decent hardware (Orinoco), XP has built-in drivers and you're in for a fight.
retrorocket.o not found, launch anyway?
I need to deploy it eventually, but my main concern right now is users hooking up an access point to their PC and using internet connection sharing or some other hack to give access to our network. So far, threat of death is working, but I can't rely on that. (We disabled ICS in AD GPOs but some users have admin rights to their PCs....)
Does 11a or 11g provide any improvements in security? All "advice" I've read about seems useless (like turning off SID advertising, easily gotten around using kismet, for example).
Do 802.11a or 802.11g fix the lousy security of 802.11b? I mean, no wireless network will ever be secure as a wired one because making it secure requires key management, but at least I should be able to expect that if I do my key management correctly, other people can't break in.
"Quick fix will let one avoid interfering with the other"
The ACA has some interesting ideas about the 5.2/5.8Ghz spectrum that don't quite agree with the FCC. For example 5.2 can't be used outdoors and the 5.8 can't be used in the long haul point to point modes and the max power leves seem to be 1/2 of what the FCC allows. The worst part about this is that the only references I can find are proposals about what they intend to do with the frequencies.
The reason for this madness is that some satellite is using 5.2 for an uplink. Considering how well regulated the frequency is in most of the countries between here and Japan, I would think it would be a very bad idea to keep a sat on a frequency that lots of people will be using.