phoneboy2
@shawcable.net
| Finally! Balanced and accurate info about WiMax
I have learned more from this one article describing WiMax than in the past year of hype. Intel should be ashamed of themselves!
Real world speeds of 802.16-2005 is 500k-2Mb/s. Not 70!
Real world distance of 5km. Not 30!
Also, it looks like 802.16-2005 (802.16e) is the standardised equipment to wait for or be upgradeable too. Sounds like lot's of NLOS improvements which is the one area I was most skeptical about with 802.16-2004.
I am now officially a HUGE wikipedia fan. Bravo Wikipedia!
»en.wikipedia.org/wiki/Wimax |
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phoneboy2
@shawcable.net | Oops, I meant real world NLOS distance of 5km for 802.16-2004, not 2005! 802.16-2005 should improve on that a bit but sounds like there are not enough real world results to state that yet. |
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godsmoke
join:2004-11-02
New York, NY
| reply to phoneboy2
I think you've been a little mislead.
NLOS is not the focus, and hasn't been, of 802.16-2005 -- the 30 mile figure is, of course, inflated marketing hype -- just like 1500 feet is with a $40 linksys router.
The speeds you referenced were just completely wrong -- you obviously didn't read the actual text. 70Mbps is a theoretical air-rate transfer PER-SECTOR, not per-client. The AT&T data rates are misleadingly mentioned -- 70Mbps is also an aggregate figure (meaning downstream plus upstream). Take 60-1000 clients (as mentioned in the article) and you have a typical 512Kbps-2Mbps per client on the 1000 range.
"Pre-WiMAX" deployments (which, for the most part, aren't WiMAX, but the performance is similar) do up to 6Mbps per customer no problem, with a handful of high-end business customers on each sector. |
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lutful
Premium
join:2005-06-16
Ottawa, ON
 ·TekSavvy Solutions..
| reply to phoneboy2
The WiMax wikipedia entry is a decent description of IEEE 802.16 rather than WiMax.
Scheduling MAC
"By contrast, the 802.16 MAC is a scheduling MAC where the subscriber station only has to compete once (for initial entry into the network). After that it is allocated a time slot by the base station. The time slot can enlarge and constrict, but it remains assigned to the subscriber station meaning that other subscribers are not supposed to use it but take their turn. This scheduling algorithm is stable under overload and over-subscription (unlike 802.11). It is also much more bandwidth efficient. The scheduling algorithm also allows the base station to control Quality of Service by balancing the assignments among the needs of the subscriber stations."
Flexible PHY options
"An important aspect of the IEEE 802.16 is that it defines a MAC layer that supports multiple physical layer (PHY) specifications. This is crucial to allow the standard effort to evolve and adapt to various types of end-use requirements. It also allows equipment makers to differentiate their offerings."
802.16-2005 vs 802.16-2004
WiMax forum pushed renaming of 802.16a to 802.16-2004 and 802.16e to 802.16-2005 even though the PHY silicon will be incompatible.
It will be interesting how they explain to customers why they really need -2004 rather than -2005.
We are lucky WiFi alliance did not name these:
802.11a to 802.11-1999
802.11g to 802.11-2003 |
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Nowireneeded
join:2004-02-11
Montoursville, PA
| reply to godsmoke
Folks, Don't slam Intel for the miscalculations of the press. I have been at just about every Wimax show in NE US in the last 4 years and have never heard the 30 mile slogan inferred to PTMP. In fact I had the opportunity to hear Mo Shakouri from the Wimax Forum in 2004 dis the press on this very issue. It's always been PTP shots. However, 30 miles is likely in the 700 Mhz band once a Wimax Profile takes shape. I'm currently seeing sector performance is the 14-18 meg sustained without overhead in a 5 Mhz channel. So in a 20 Mhz channel +70 meg's of real sector performance can be achieved and it's how you divy it up that matters. 2 to 1 frequency reuse is another example of how Wimax and new antenna technologies are taking our industry to the next level. |
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Nowireneeded
join:2004-02-11
Montoursville, PA
| reply to lutful
"802.16-2005 vs 802.16-2004
WiMax forum pushed renaming of 802.16a to 802.16-2004 and 802.16e to 802.16-2005 even though the PHY silicon will be incompatible.
It will be interesting how they explain to customers why they really need -2004 rather than -2005."
Those deploying 2004 today are kicking the tires and/or may not be interested in Mobile wireless. 802.16e "ready" gear will hit the streets by end of this year. "Ready" meaning the silicon will be Intel Rosedale 2 and upgradeable to full "e" interoperability. I do agree that the naming of these protocals is pretty silly. |
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phoneboy2
@shawcable.net
| reply to phoneboy2
Seems to me that anyone spending serious money on 802.16-2004 is throwing their money away. Unless the equipment vendor offers an economical upgrade path to 802.16-2005 and assuming 802.16-2005 lives up to its promise on the improvements which it looks like it might, it looks like 802.16-2005 equipment is worth waiting for.
Godsmoke, just how are their statements (on end user oriented websites mind you, still splattering this BS all over the place to this day) clearly stating "up to 70mbit/s" at "up to 30km" NOT misleading. It's far beyond misleading, it's a blatant lie! If you don't believe me look at the Intel and NextNet websites. I am an Electrical Engineer and I sure as hell find the statements misleading. You are simply trying to justify how they come up with the numbers. It does not let them off the hook for INTENTIONALLY misleading the masses into thinking that is what each of them will get on their PC at home.
Radlink, Huh!
What part of "WiMAX is an acronym that stands for Worldwide Interoperability for Microwave Access, a certification mark for products that pass conformity and interoperability tests for the IEEE 802.16 and ETSI HiperMAN standards." Did you not understand?
I should have known, post what I thought was the difinitive article on WiMAX and people will find more things to disagree about just for the sake of disagreeing! |
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phoneboy2
@shawcable.net
| reply to phoneboy2
From what I have read, Wikipedia is not just a hodge podge of people posting info like a typical Wiki. It supposedly get's filtered through a select group of people before the final product get's out. That WiMAX article is a lot better than anything else I have read out there. They have no bias towards or against WiMAX like just about all the other info out there and it really shows IMHO. |
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cmaenginsb
Premium,MVM
join:2001-03-19
Palmdale, CA
| reply to phoneboy2
Phoneboy 802.16-2004 and 802.16-2005 are two different technologies with 2 different goals. You deploy the type of equipment that suits your needs not what the current "fad" is.
If you are looking to push high capacity wireless out for a longer range then 2004 is the better choice where if you want indoor installs with the lower throughput and range then go with 2005. The 2 different technologies are similiar to 802.11g vs 802.11a both have their place in the marketplace for different reasons.
BTW 70Mbps at 30 km with LOS is easily doable.
--
CCNA, Comtrain Certified Tower Climber |
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phoneboy2
@shawcable.net
| reply to phoneboy2
Perhaps btw two high towers with good quality highly directional antennas in a backhaul type situation. I'll buy that.
That is NOT what they are implying. They intermix it with talk of tower to CPE. Not outdoor CPE either but I'll let that one slide as just marketing embelishment. There is nothing I have read that attempts to make the distinction or to clarify the IMPORTANT distinctions. It's not an oversight or mistake or poor wording IMHO. It is a deliberate misrepresentation. |
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phoneboy2
@shawcable.net
| reply to phoneboy2
From what I have read, mostly from that wikipedia article, 802.16-2005 has all the advantages and meets all of the goals of 802.16-2004 plus enhancements in NLOS and for mobile type applications as opposed to portable fixed wireless. Sounds like they fixed some of the shortcomings they found in real world testing of 802.16-2004.
They did mention something about lower power but were not too clear on that. Maybe it's not as good for backhaul applications which does not affect most of us anyways.
I'd be interested to hear more about the differences if anyone cares to elighten me. |
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lutful
Premium
join:2005-06-16
Ottawa, ON
1 edit | reply to phoneboy2
Phoneboy, did you notice my edits at the top of the wikipedia WiMax page? |
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phoneboy2
@shawcable.net
| reply to phoneboy2
I found another article that gives some pretty good information. It's a bit dated(Nov2005) but still a good read. They basically seem to say the same thing. Everything will migrate to 802.16-2005 with the new equipment remaining backward compatible with 802.16-2004 if someone want's to continue to operate in that mode.
I found their analysis of transition paths to be interesting. They are saying that CPE's will eventually support both which allows the operator to use either/or depending on what makes the most business and technical sense.
I failed to read anything in there implying that 802.16-2004 was capable of doing anything better. Just that it is here now and because it's less complex than 802.16-2005 it will be cheaper in the short term. In the long term they say 802.16-2005 equipment will be cheaper and since it will all be capable of operating in either mode it will be a no brainer. Again, I am strictly talking Tower to CPE. Not backhaul. There is tons of equipment available now that can do that just fine and will not benefit from 802.16-2005. |
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phoneboy2
@shawcable.net | reply to phoneboy2
Oops, here is the article
»www.senza-fili.com/downloads/Sen···aper.pdf |
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