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Australian WiMax Pioneer Calls It a Disaster
Anonymous Coward writes "Garth Freeman, CEO of Australia's first WiMax operator, sat down at the recent International WiMax Conference in Bangkok and unleashed a tirade about the failings of the technology, leaving an otherwise pro-WiMax audience stunned. His company, Buzz Broadband, had deployed a WiMax network over a year ago, and Freeman left no doubt about what conclusions he had drawn. He claimed that 'its non-line of sight performance was "non-existent" beyond just 2 kilometres from the base station, indoor performance decayed at just 400m and that latency rates reached as high as 1000 milliseconds. Poor latency and jitter made it unacceptable for many Internet applications and specifically VoIP, which Buzz has employed as the main selling point to induce people to shed their use of incumbent services.' We've previously discussed the beginnings of WiMax as well as recent plans for a massive network in India.
Because my old tube radios will survive the EMP, I'll still be able to listen to the static.
Why can't we go back to using jumpers to configure slot adapter cards? Why? I say!
I am no RF expert either, but I have been on the receiving end of WiMax-ish technology, and the jitter was so bad, it was completely unusable for VoIP and even made ssh annoying at times.
This was kit designed to work for up to 10 km (6 miles) and I had line-of-sight to the base station, which was about 150m (500 ft) away.
Sky.. sky.. SkySomething. SkyPilot? Some kind of wierd meshy-network, I was also connected to the "master" tower, not a leaf.
The problem, as it was explained to me, was that it has a collision/backoff algorithm not unlike that of 10-base-2 ethernet ("thin net"). So, the 50 (or so) neighbours I had, plus the leaf towers (2 of them, I think) were causing me to not get "slots" with the master on a timely basis. Hence, introducing jitter.
So, your L2 protocol hypothesis is reasonable from my perspective, although we can eliminate poor radio performance as a direct cause. Changing the radio from broadcast to something like time or code division multiplexing would be a good solution for reducing jitter, but probably causes other problems (like decreased burst bandwidth and range).
My solution? "*sigh* - cancel the wireless link and order me a up a T1"
Wireless is nice because it's easy. But it sure ain't there yet.
Do daemons dream of electric sleep()?
AM radio spans roughly 1 MHz (IE: approx 530KHz to 1.6 MHz.) You CANNOT fit a broadband wireless service into that space ... furthermore, the resonant antenna length for 1/4 wave varies between (approx) 150 metres to 40 metres. Like to see you stick that out of the back of your Laptop.
... okay for Laptop, (easy)
...)
doubtful if you could effectively get one 54mbit channel in that space, plus, because it is NOT line of sight, someone a few miles away WILL interfere with your local transmissions.
Low frequencies (below about 2 MHz) hug the ground, this means AM does not have line of sight issues. Some AM broadcast stations have service areas of hundreds of miles (kilometers) (radius)
FM is 88.. 108 MHz. 1/4 wave here is roughly around 1 metre. Still a thumping huge antenna! These frequencies are considered line of sight, however, there is a small area extending beyond line of sight. Enough bandwidth for a few 54mbit channels.
WiFi is generally at 2.4 GHz. Same band as Microwave ovens use. Has to do with the frequency of maximum absorbance of water. (Thus used in ovens!) 1/w wavelength approx 4 cm
To get sufficient bandwidth, only UHF and up is really useful. But, get too high in the microwave band and the signal wont even get through a thin wall.
So, there are trade offs that genuinely make sense for wireless broadband. (lots more reasons as well
I chose as my ISP in Mexico City E-go, co-owned by Alestra, the Mexican AT&T subsidiary. It started offering WiMax connection in 2003 in limited areas of Mexico City (I understand nowadays it covers most of the Central, Western and Southern parts), before even WiMax was standardized. Clients get a NextNet RSU unit, which is basically a network bridge. :) E-go owns 20MHz of spectrum, which allows it to give a theoretical maximum of 70Mbps to a given area. If many too people were to subscribe, each client would have much less effectibe bandwidth alloted.
The latency complaints you state are simply not true - I get consistent ping response times of 100ms in average (with minimum response times of around 50ms) to hosts in Mexico City, 200ms to hosts in the USA. Yes, this is about 80ms higher than wired equivalents - but it's not so much of a killer. What I do get, of course, is way higher packet loss - About 5% when things are optimal, and it sometimes gets up to 50%. But yes, I'm located at a relatively poor reception area, at one of the lower-income (this means, no incentive to place many antennas nearby) neighbourhoods in the South of the city, where the mostly flat valley where most of the city is located begins to become quite hilly. The RSU unit does not provide any means (for the client) for monitoring connection, to help choose the best possible location. It only has five LEDs (and no, they are not blue, just an unfashionable old green. Bummer.) indicating signal strength, and I always get one or two of them. I have seen signal quality significantly better when at a five-leds connection.
Prices and speed are more or less in-par with Mexico's near-monopoly TelMex; I'm paying about US$40 for a nominal 1Mbps/128Kbps connection (512K guaranteed, whatever that means). The upstream data flow _is_ shaped to 128k, but the downstream speed is not - when the network smiles on me, I get up to 2Mbps. It is not common, though.
I understand E-go (back then called I-go, don't ask me why) was praised as the world-first massive WiMax deployment - Even before the standard was finalized. There are several aspects of the installed network that show clearly the gear is pre-standard (i.e. extreme sensibility to position changes - If I move my RSU over two centimeters, it has to resynchronize with the antenna. This process takes around two seconds, so no big deal).
To me, clearly, the reason it hasn't got more popular is because it is owned by a relatively small company, and has not had the muscle to stand in front of Telmex's publicity machine.
Of course, we benefit more than DSL users from having a low client density
There's nothing magical about WiMax. Other frequency ranges, other protocols, that's about it.
The only interesting thing about it is that it's not operated by traditional telcos.
But remember, what traditional telcos sell is not telecom, they're SELLING UBIQUITOUS telecom.
An untraditional telco would have to sell at a nonzero price ubiquitous. If they sell at zero price (or truly flat rate), a smartass will monopolize all access and resell it at real market price (what people are truly willing to pay). If the service is only sporadically available, no one will want to pay for it, or they would be better off setting up a fix line connection at the only place it works. If they comply to the two conditions, they are definitely traditional telcos.
In the long run, WiMax is bad for the consumer. As I explained above, the business model behind WiMax can only be the "traditional telco model". But now we have two technologies with incompatible end user hardware, incompatible operator hardware. Nokia and Alcatel Lucent will sell less copies of their products to operators, thus the price will rise. Nokia and Alcatel Lucent will ask for higher fees from the opco, guess who will pay the bill. Nokia and Motorola will sell less copies of their products to end users, guess who will pay for the relatively higher cost.
Furthermore, with WiMax vs 3G, there are now not one, but two markets for mobile data and voice. Barrier to jump from one to the other market is nonzero for the consumers. Each of the individual markets is also smaller, hence less competitive.
Fuck WiMax