
problematic
"but radio frequency physics remain problematic"
Bummer, they should work on that!
Australian wireless carrier Buzz Broadband has shuttered its WiMAX network, describing the technology as a "disaster" that has "failed miserably". Speaking at an international WiMAX conference in Bangkok, Garth Freeman, CEO of Buzz, claimed the technology didn't work indoors more than 2Km from the base station and had latency …
Radio frequency physics doesn't account for latencies of 1s.
What might account for excessive latencies might be things like using a DSL network for backhaul from the base stations, especially if they were "brave" enough to attempt it with a national ISP's network. No idea if that's what was happening here, but heck, some 3G companies are using DSL for backhaul (or talking about it) [1]. Try that with your favourite VoIP client .. and .. see .. how .. well .. it .. works.
Even so, and even with the world's worst VoIP codecs, 1s latency seems a bit excessive.
Stuff should generally be used for the stuff it was designed for. E.g. voice calls go over voice networks (wired or wireless), unless you're makiing enough simultaneously to need to invest in proper quality bandwidth for VoIP (which doesn't mean residential-class DSL).
[1] http://www.theregister.co.uk/2008/01/16/adsl_backhaul/
Using "DSL" lines has been used for years by carriers. Ever heard of a T1? They run those over "DSL" and it is not what you think. The Internet has nothing to do with it. You can have P2P DSL lines.
The carriers like the DSL T1 lines because they only use one pair instead of two. Copper is expensive the DSL T1 lines also allow them to troubleshoot the remote end and get more information about line quality.
Oh, 3G also has more latency than EDGE/GPRS.
Look, WiMax is WiMax. You understand the technology and its shortcomings. So you use it where you know that you don't have the shortcomings.
The promise of WiMax is broadband speeds without the wires.
So you set up your WiMax antenna by the window or outdoors (depending on the antenna) and you the have your hub/switch/wireless intranet access point to your network.
Does this limit the applications? Maybe. But if the price is right, its a lot easier to set up than the last mile of cable, and dealing with some of the local telcos who promise one thing, but fail to deliver.
If you want VoIP, then sure maybe WiMax isn't what you want. But if you need a T1 for an office internet connection... maybe it is. We won't know until you do a price comparison. Also, if you are changing locations... You can always move the equipment. You can't do that easily with a T1.
No?
The flame because articles on the failings of a technology when its misused is not a good thing.
And if reception still isn't good keep moving the antenna a little closer to the base station... in fact why not run a wire all the way. Just look at it as a wave guide. It's still wireless, just the wireless waves are kind of directed to you personally - very elegant solution actually. Just wait, someone's marketing department will latch on to this idea...
Mountainous Spain with well-distributed communities has an excellent record on WiMax. My house uses a link perhaps 15 kms from the base station; I have a square microwave directional antenna on the roof and a four pair cable ethernet connection from that to my PC. The only time the link goes down is during extreme weather conditions such as torrential rain. I would not change it for the world and especially would not replace it with a broadband connection via the hopeless Telefonica phone company.
Looks to me like Airspan has to take at least 50% of the blame for this failure. Why weren't Airspan's customer service intimately involved with rolling out this service? This is complicated stuff especially to new customers. Why didn't Airpsan demonstrate to the Buzz Broadband how it would not fulfil their needs on latency and coverage. Why sell them equipment knowing their network would not work. Surely this bad press will cost Airspan more than they gained from the contract with Buzz Broadband. I think Airspan is at least equally culpable for this failure anmd they should look at their head of customer services or whoever is responsible for assisting customers with rollout of service.
There isn't any technology that will do decent indoor coverage at 3.5Ghz. Just compare how much worse 2.1Ghz 3G is indoor than 900MHz GSM. A basestsion on 3.5GHz that gives 15km range on chimney aerial is unlikely to do even 2km indoor, unless your room has a big window with LOS to mast.
It's the frequency & expectation that is wrong. I'd not be surprised if Airspan did warn Buzz, but people hear what they want to hear.
Incidently I do frequent runs to see what speed I'm getting from Iberbanda S.A., my Spanish provider. I only signed up for 512Kb (WiMax in Spain is more expensive than via Telefonica's phone lines so I took the lowest speed to save money) but I consistantly get over 500Kb both up and downlink.
My friends on Telefonica's broadband-over-telephone wires who have signed up for a 1Mg connection ran the same test and found on average they were getting 300Kb up and 600Kb down. Their perception of my 512Kb connection is that it's faster than their 1Mg connection. Kind of obvious......
well, at present it seems to do so in Italy, <http://www.ngi.it/eolo/bts.asp>
the root address at www.eolo.it (only in Italian, sorry) explains how you can get up to 12megs via an external 5GHz antenna. My friends use the 2 meg service and only complain that their 600 euros per year unlimited data contact has to be paid up-front when signing the contract. Of course this almost WiMax wouldn't be needed if T*l*com It*lia would actually deliver DSL to non-metropolitan customers.
in keeping with El'Reg's excellent technical hive knowledge I will reveal that the Eolo network uses about 8500 client Alvarion BreezeACCESS VL LOS/NLOS dishes with wideband OFDM at 5,4-5,7 GHz point to point to 62 usually mountain-top Motorola BTS with fibre connectivity at 10Gbit/s to the NGI backbone via Cisco 12410 routers with 4Gbit/s to the Internet. All allegedly independent of Telecom Italia.
for those who like Antenna Pr0n, try <http://www.ngi.it/eolo/fotogallery/images/bts_campodeifiori/3.JPG>
1.JPG, 2.JPG & 4.JPG for images of Italian pre-alps, lakes and yes, Antennas!
Buzz Broadband used 3.5GHz spectrum for a Fixed WiMAX service which requires line-of-sight, while Sprint will use 2.5 GHz spectrum for a Mobile WiMAX service which does not require LOS and also penetrates buildings better. Airspan also separately issed a rebuttal on the situation.
Lance wrote "Oh, 3G also has more latency than EDGE/GPRS"
Not true. GPRS is about 700ms round-trip ping times, Rel99 3G about 200ms, and HSDPA about 130ms. Try it by pinging a server if you don't believe me.
There is a difference in their cold-start peformance - 3G escalates the connection speed through a number of steps each time upgrading the mode and bandwidth. These transitions can take a 1 or 2 seconds to complete - and so for a small amount of data such as a very simple webpage GPRS can beat 3G - but it quickly loses this advantage once the download exceeds a few tens of kilobytes.
Very surprised to learn Buzz's WiMax had a latency of ~1second. Sounds like a problem specific to their network (congestion, overloaded equipment?) unless others can confirm this is generally true for Wimax?
I just experimented with ping times on both 3G and EDGE connections.
Huawei 3.6mbps 3G USB modem on the 3 network (the software claims 2 of 4 available signal bars) had ping times to 66.249.91.99 (a Google IP address) at 134ms, 134ms, 133ms and 133ms. A HTC device using USB internet sharing on the O2 EDGE network (the phone claims 4 of 4 available signal bars) had ping times of 886ms, 675ms, 832ms and 730ms.
I don't know what explanation there is for that, be it technological differences, backhaul or what, but that's a pretty marked difference.
"Alvarion BreezeACCESS VL" is a product that uses a modified Wi-Fi MAC - there's not a trace of WiMAX in it.
There is no "5.4-5.7GHz" frequency profile in WiMAX
What do the "Motorola BTSs" do in this network? They certainly won't talk to Alvarion clients.
How do they get 10Gbit/s fibre to the top of mountains?
I'm guessing it's actually an Alvarion access network with Motorola backhaul connections at a few 10s of Mbit/s.
There is a world of difference technologically between a low density rural network serving clients with external directional antennas and a high density urban network serving clients with low gain antennas usually mounted indoors, although I would say that both have to be executed very effectively to make money.
So our friends in Spain and Italy get good results from fixed, outdoor, line-of-sight connections. This is basically the same as proven established microwave link technology, albeit carrying IP network traffic and using a fancy modulation scheme.
What remains to be seen is whether WiMax works for mobile and in-building coverage.