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Wireless Networking at 72Mbps
Unknown Relic writes "One of the biggest drawbacks to current wireless networking technologies is the limited connection speed. Well now LinkSys has released a new wireless access point which operates on the 5 GHz band, supports up to 72 Mbps connections and is fully interoperable with existing 802.11a wireless equipment."
adam
That means 7 times more of my packets can be sniffed than if I used the traditional 11Mbps technology... -mg
Contrary to the post, I would argue that connection speed isn't one of the biggest drawbacks. Rather, it is the lack of standards and interoperability.
Testing reveals that most of these "802.11a" access points are not compatible with each other. Only identical products work together. So when your vendor EOLs (End of Life's) your AP, further expansion of your network becomes a problem.
Several companies have announced 802.11a cards that use two channels and get up to 108Mbps. But as The Register article mentions there is considerable overhead with wireless ethernet. 802.11b (11Mbps) typically gets 5Mbps real bandwidth, 802.11a (54Mbps) gets 23Mbps real bandwith, and 2 channel 802.11a (108Mbps) gets 34Mbps real bandwidth.
7 31 . tml0 2.htm/ 8450/
http://www.theregister.co.uk/content/archive/22
http://presslink.dlink.com/releases/pr01-07-
http://www.proxim.com/products/all/harmony
"Up to 54Mbps" Check out the data sheet: ftp://ftp.linksys.com/datasheet/wap54ads.pdf
Technology advances seem to only happen when I adopt the old standard. Eleven seconds ago I successfully installed plain old 11.b onto this box.
DLink is also selling a 72 Mbps version, and Proxim is selling a 108 Mbps version of this same product.
I'm using the D-Link. It works, but I haven't benchmarked it for speed. It says it connects at 72 Mbps consistently.
Intel and SMC sell 802.11a equipment too. The Intel one is limited to 54 Mbps. Not sure about the SMC.
Best thing for me is that it doesn't interfere with my analog 2400 Mhz devices because it runs at 5 GHz.
From the linksys page:
"* Operation in the uncrowded 5 GHz band"
Yeah, uncrowded because nobody has really launched any of the unlicensed wireless gear there. Give it a couple years like 802.11b and then we'll see how uncrowded it is.
(still, having more channels in 802.11a is nice - really nice)
yack0
-- There is no sig line, only Zuul.
is fully interoperable with existing 802.11a wireless equipment.
Uh, no kidding. The 802.11b standard is the slower, ~11Mb/s one. 802.11a is specced to be faster. The Linksys product is just a regular access point for 802.11a.
Is this one of thaose Slashvertisements I've been hearing so much about?
--saint
And, if it has the range that 802.11 is *supposed* to have, we'll all be happy. But, if it behaves like current wireless devices, I'll need two WAP's in every room of my house.
Imagine my disappointment after reading about 802.11 and getting a WAP and card for my Zaurus thinking that I could walk around my block with an instant messenger app running. As Topsy says, "Forget about it!" I couldn't walk to the other side of my house.
As I'm sure most of you already know, beware of claims of bandwidth and range...
but compared to gigabit ethernet, it's really not all that fast, particularly when you start splitting it over an office or some such.
Hexayurt - open source refugee shelter,
so not true, in a big corporate sales/marketing/feedback system only really pissed people get through (unless they're mining their DB for a marketing campaign, then they read the too-much-prozac-this-morning happy ones). Or people with an original take (like 'hi mr. tech support marketing guy, my name is d3v0 and i just found a way to hack your access point to broadcast porn across local public access TV broadcast frequencies'). Or, best of all but also most expensive, people who have letterhead with their name followed by esq.
closed minded is as closed minded does
It says right here (warning, PDF) on page 4:
Minimum Requirements
One Pentium Class, 200MHz or Faster, PC equipped with Windows 98, Millennium, NT version 4.0, 2000, or XP, 64 MB RAM...
And on the card homepage it says (in the last paragraph):
"Ready to run in Type II or III PCMCIA CardBus-equipped notebook PCs running Windows 98, Millennium, 2000, and XP..."
It's not likely that many people who want fast wireless would still be running Windows 95 or NT4 on a laptop anyway, so that makes sense.
I'm going to resist the urge to question why you would want to run Windows 98 or ME over Windows 2000 anyway (I'd give up the 10% speed increase for stability any day), but either way, you're wrong about their driver support.
By the way, if you want to be taken seriously with your letter of complaint, avoid the use of "kinda" and "sorta".
Simpli - Your source for San Jose dedicated servers and colocation!
You should be nice when dealing with reputable people. That "Virtually All" line wasn't marketing spin, it was an outright lie. Only when we have the self confidence as consumers and citizens to start calling companies and politicians out when they 'pull a Clinton' like that do we have a chance to deal with them as equals in a free market/society.
They showed zero respect for our intelligence so why should we respect them? Respect is NOT a right.
Maybe you like holding the ankles and swallowing aything a company puts on glossy paper but I sure don't. Linux has only marginal relevance in this case. When I read "Virtually All" I expect to see more than three entries on the list. Obvious omissions are PowerMac (Powerbooks have Cardbus slots you know, and OS X certainly qualifies as a Network Operating System) Netware, Linux, *BSD and SCO.
And yes, there ARE times when running any/all of those in a wireless environment is useful. Think portable training lab for a second. Think portable data gathering.
Democrat delenda est
That I'm going to miss running category 5 cable, who's with me? Now just to find out what these things cost... ok, I'll be running Cat5 for quite some time to come :-/
...and the bandwidth creeps up a little more. Soon soon soon I'll have wireless everything. Keyboard, mouse, monitor, speakers, sub, and network access.
:D
As a bonus... I can reheat my lunch by propping it up in the middle of all this
a grrl & her server
This is all fine and dandy but until the encrytpion is strong enough that I can use it on my company's internal network myself and many other admins can not consider it.
5 0a p/prodlit/1281_pp.htm
Cisco has a dynamic WEP key solution that sidesteps WEP's vulnerabilities
http://www.cisco.com/warp/public/cc/pd/witc/ao3
and I think Proxim has a similar solution, but I don't think either solution is interoperable with other manufacturer's equipment.
Does anyone know if there is a standard for dynamic WEP keys that works across multiple vendors?
Here are a few tidbits of FACT that you can also process in your haste to flame LinkSys...
. html and you will find that under "Drivers Available" they state: "Source code may be licensed to facilitate design-in for non-PC platforms." But don't get too excited. I'm sure you will have to sign an NDA and convince them you're gonna buy a truckload or two of cards. And I'm also sure you will find that Atheros has bound their hands also, with respect to low-level technical info needed to write a Linux driver.
:)
a) Until quite recently, the only chipset available from which to build an 802.11a radio, either user or access point, was from Atheros. Now, Resonext has released a chipset and someday (soon?) Intersil will release their Indigo chipset for 802.11a. At present, you can almost be certain that any 802.11a product you can buy uses the Atheros chipset.
b) Atheros is being VERY tight with tech specs. You most assuredly would have to sign an NDA, and probably sign a purchase agreement, committing to buy 5 to 10 thousand chips before they will THINK about letting you peek at the technical info you need to write a driver.
c) An Atheros employee told me in March that a Linux driver was under development, and would be out in "a couple of months" (so it's due, like, now).
d) Proxim sells an 802.11a Mini-PCI card as an OEM product. See: http://www.proxim.com/products/all/oem/9350/index
c) The 72 Mbit/sec "Turbo" mode is a feature of the Atheros chipset -- Linksys just inherited it by virtue of using their chip.
And finally...
The 54 Mbit/sec (or 72 Mbit/sec "turbo") is extremely range limited. At 100 ft, 802.11a drops back to a speed which is very close to 802.11b. But there are many reasons (other than raw throughput) that 802.11a is a Good Thing (tm), so let's look on the bright side that we have it.
And by the way, let's tip our hats to Apple Computer for supporting the efforts in its advanced technology team to petition the FCC for unlicensed spectrum. I was there. I can tell you that Apple deserves praise for paying the salaries of people who did nothing but work toward getting unlicensed spectrum (e.g. U-NII, where 802.11a operates) available for us geeks
I recently got a new wap11 v2.2 from linksys to put in my office on top of the server racks so I can just sit back in my chair, with my feet up on the server racks, and surf the net with my laptop. Anyway. Whenever I get a packet collission with it, the wap11 v2.2 stops transmitting packets.... odd huh? Linksys support jerked me around, and I got moved to 2nd level support once I called one of their support persons on the bullshit they emailed me. She told me to set the wap11 v2.2 to values that are not even possible to set. Anyway. I was recently emailed a new firmware image, so instead when it gets a collission, it sometimes resets, but If I'm lets say 20 feet away, Its useless, the link won't work. Atleast they have not tried blaming it on my linksys wpc11 cards.... but they did tell me to flash the pcmcia card with the most recent firmware... my response was "Didn't you know, you guy's don't let people download firmware images for your pcmcia cards". Gee... I wonder what they will send to me next week.
Just one thing, Brick walls are death to wireless ;o)
When you say "the media", I think you mean "Slashdot".
Ask your parents what they've heard lately about "war driving" and they'll tell you horror stories about the L.A. highways.
No. If you're not using VPN software you're incompetent. WEP is garbage, and SSID is sent in the clear.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"The problem with 802.11a is the high frequency in which it opperates. 5ghz is just too high for anything other than line-of-sight (outdoor). The 2.4Ghz band that 802.11b/g opperate on is still high and still suffers from line of sight limitations, but in general, it fares better.
I also have to wonder, who needs that much bandwith in a wireless application? Perhaps you should really be thinking about a wired connection if bandwith is that critical. In most applications, it's not the standard that's the major limitation, it's the equipment.....most cheaper cards are not full-duplex....so you're missing half your bandwith right there. Good equipment and antennas will serve you much better than a "better" standard.
1. Don't get two Linksys WAP11's and put one of them in Access Point Client mode. You will have to reboot that access point nearly every day because of firmware bugs (even with the latest firmware). Not bitter.
2. Get as close to a line-of-sight path as possible. You need at least an -83dBm signal to do 11mbps, so shoot for -75dBm during install if you want to maintain -83 when people walk in front of it, it rains, etc. Shooting through glass or drywall doesn't hurt very much (I've gotten -75dBm between an Orinoco Silver and a Dlink DWL-1000AP with 10 sheets of drywall in the way and stock antennas) but thicker things like concrete really hurt. So do more than a couple trees (the drops of water that tend to hang on their leaves some of the time are opaque at 2.4ghz).
3. If the only way to get a usable line-of-sight is to mount something on the roof, then do it, but keep cable runs to an absolute minimum and use LMR400 coax. Install properly-grounded lightning arrestors where the coax enters the roof. As for the antenna itself, you can weatherproof just about anything by putting it in PVC pipe or you could get a dish, panel antenna, or yagi from any of these people.
4. Security - since WEP sucks, you'll want to do a VPN of some sort between networks. You'll probably want to spend a few weeks learning how IPSec works on the systems you'll be using as your routers to accomplish this. I would recommend against any of the VPN appliances as a lot of them are too stupid to do things like put the default route across the tunnel.
Death, n. At least 12db signal loss. See also: cinder block, forests, high chain link fences, 2.4ghz wireless phones, and malfunctioning microwave ovens.
Does the 5GHz frequency mean that my Pringles can won't work anymore? Anyone have some recommendations on some tasty antenna packaging system for 5GHz?
Do you give your instructor back rubs by any chance?
- Toby
SSID and WEP are completely independent. SSID does not raise the security level in any way, although it might look like it does.
As far as I can tell, SSID is just a convenience feature to keep different groups of users separate even if they happen to be on the same channels.
WEP is an encryption feature based on RC4, but it turns out the protocol is flawed- there are a couple of cracks out there that can crack it in under an hour.
In contrast VPN software can be arbitrarily secure; as the security is at a level above the wireless transport level, basically nobody can read the encrypted contents of the packets- VPN software is frequently across the internet for that reason.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"