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Is VOIP Over WLAN DOA?
prostoalex writes "Voice-over-IP in Wireless LAN environment - a futurist's dream of always-on always-connected service. Guy Kewney from eWeek tests the technologies that try to satisfy this market today and finds nothing but disappointment. " The best result we got was that just once, I heard his voice with a delay of about 15 seconds, saying "You just have to speak up!"--which was part of a 20-second burst of speech from him. The rest was lost.""
VOIP over WLAN is not DOA. If you tweak the QOS etc settings and don't just throw things together haphazardly, then it works beautifully. Personally, I just wire VOIP to a cordless phone, then let the phone handle the wireless part. Enough of the ____ is dead articles.
I hate sigs.
First off, it's eWeek for crying out loud! Second, it's still too early to proclaim VOIP over anything (WiFi or Ethernet or whatever) dead. Second, I have seen it work and it worked wonderfully. Declaring VOIP over WiFi dead is like saying Apple's dead because it does nto have the market share that Dell does.
Gorkman
...just use a phone?
Dear aunt, let's set so double the killer delete select all
I know a guy that just had problems getting KDE to work with his video drivers. Does that mean I can submit a story titled 'Is Linux dead?' and see it published on Slashdot?
I'd like to visit the magical world the submitter lives in where every new technology works perfectly from the get-go and never needs to improve and be developed. Must be nice.
... what would have happened if during the invention of the telephone, they all became put off and declared "Voice over Wires DOA" just because the 2nd test wasn't perfect.
It's not like this is as good as it's every going to get. If that was true, EVERYTHING would suck.
Slashdot sucks
Your post is an excellent example of what's wrong with VOIP at current.
To use a telephone, you go to the local thrift store, spend $5 on a phone, and plug it into the wall to get reliable telephone service.
To use VOIP, you have networks, hubs, routers, wireless cards, firewalls, switches, and enough power bricks to saturate two 6-plug power strips so that you end up with something that must be tweaked to operate smoothly at all, in order to get something with the range of a cordless telephone. (Wifi uses the exact same frequencies as a cordless telephone - it's essentially a fancy cordless telephone modem)
Never mind what happens when any of those various boxes have a security vulnerability found...
In order to be truly successful, the technology needs to GET OUT OF THE WAY for the common user. Bridges are technology that are so reliable we never think about using one. So are telephones. VOIP will have "arrived" when it's use is automatic and reliable.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Maybe one day, but right now the technology isn't there, and the need/reason/means isn't that strong in a lot of ways. People have cell phones, and for most those accomplish all that is necessary. There are already devices connecting over cellular networks that can accomplish everything needed for many people.
Down the road I bet the networks will mesh together, and the wifi, cellular and others will start to be one big network operating in small clusters to keep things running smoothly. We can't handle that kind of bandwidth and that many users now, but who's to say we won't be able to in 20 years?
I just doubt that the separate wifi and cellular (and other) standards will persist side by side for all that long as convergence quickens.
Presently here, but not there.
Technology needs time to improve and mature. This is something we refuse to accept today.
Yes, to use your OWN telephone. But if you want to telecommute and be on the corporate PBX, VoIP is the ultimate solution. You can have the same number for days when you are in the office, at home, or on travel. All calls you make come out of your office PBX and not your home phone.
You can get (pretty much) all of these advantages with a cell phone, starting at around $35/month.
Oh, wait a minute. Aren't we talking about wifi VOIP? Isn't a cellular network just another wireless network?
Here, in Chico, CA (Near Sacramento) we can get a cell phone with a company called Metro PCS and you get unlimited calling, though your coverage area is somewhat limited.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
If you RTFA, the guy is whining about latency. Wireless, in this case 802.11, and specifically Direct Sequence Spread Spectrum digital transcievers often employ more than one forward-error-correcting protocol to get around the horrible bit-error-rates. For most packet traffic, a little latency is an acceptable price to guarantee that more packets pass their checksum. For streaming audio/video this is not so.
Not knowing exactly what was going on, I'm going to guess that his connection was really bursty, possibly due to other 802.11 traffic and also possibly multipath interference aggregation problems with many RF sources in the same band in a confined RF reflective space. If I were a latency-sensetive streaming protocol, I would buffer a little bit, and cut out a lot. I'm thinking I would probably flush a lot of bytes from my buffers because they got too old before I could assemble a meaningful blast of audio.
If this kind of thing sold access points, then 802.11 chipsets would have a sideband that tolerates more packet error and less delay. That would allow you to turn on "interference robustness" and still make a phone call because it doesn't use "interference robustness."
--- Nothing clever here: move along now...
1 or 1.5 seconds is not ok for any type of real telecom, maybe for walkee-talkees but not phones.
/ mo s/
The telecom industry spent a lot of money to find out what people find is OK. The two main factors are delay and Mean Opinion Score (MOS).
For delay anything past 300ms people will notice, around 500ms you start to hear echo. Most phone service worth it's salt will keep it below 300ms.
MOS is a 1-5 score placed on the quality of the voice through a connection 1 being low, 5 being excellent. More info:
http://www.tech.plymouth.acuk/spmc/people/lfsun
So when the author states that it's not ready for prime time its because a 1 second delay is actually at least 3 times too long. If you can deal with it, more power to you, but the telecom industry would laugh at any company who would try to bring 1 second delays to market.
ft
Yes, all the carriers use VoIP on their backbones, about as controlled an environment as you'll find. The real question is VoIP to the endpoints, particularly over wireless. The answer is -- it's doable, but you need a much more aggressively correcting implementation than what's commonly deployed.
Cell nets aren't LANs, btw -- they're either MANs or WANs. There are real differences -- in protocol, in problems, in nature.
--Dan