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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.""
At work i use my Cisco 7920 wireless VoIP phone. We are in the middle of a remodle of the IT department and it works great. I've had very few issues.
I'm a cucumber
Me? I use Zalman headphones with a logitec webcam microphone duct taped on the right side. But I just use it for gaming. If I had to communicate anything other than "Our base is 0wn3d!" I would probably get something better.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
75% of my day is surrounded by WiFi access, however, that access is not always free (Tmobile, Leap Auth., Hotel services). I think that the problem with VOIP via WiFi is just that - not all WiFi is free. If we had free WiFi everywhere, then carrying a small VOIP would be cost effective, but would I throw away my cell phone? No. What if I broke-down on the side of the road? VOIP WiFi has no regard for those "emergency" situations. However, I would definitely get rid of my current VOIP "land line" and buy a WiFi model that I could take with me instead.
On another note, Im trying to get some users to a new website I created. It is basically my "day trading" stock journal online. Everything is free of course, so if you like stocks, I recommend taking a look. GroupShares.com.
Thanks,
Aj
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artlu.net
Sounds like this could be fixed with some QOS (Quality of Service) software. Prioritize the VOIP and deprioritize things that are not of a time sensitive nature, such as email, and the call won't lag.
I've used Skype ( http://www.skype.com/ ) quite extensively (windows only at the moment but they have a linux version in the works) over my LAN and via my cable connection to people ranging from 160 miles away to people in other countries.
Sure, there is a slight "houston, this is tranquility base) type of delay, but within a couple of hours use this becomes second nature.
Many of the calls I made exceeded one hour in duration, god alone knows what they would have cost via telephone.
Every call was end to end encrypted, yes, even the voice signal.
To call what is effectively a brand new technology which is basically still in public beta DOA is nothing other than complete and utter bollocks and a sure sign that whoever is applying such a label to VOIP is either...
a/ terminally fucking clueless
b/ blunkett (UK) / cheney or rice (US) / a telco shitting themselves.
BT has just started rollout of 21CN which will involve the ENTIRE NETWORK moving over to IP based traffic routing, so some 30,000,000 telephones in the UK alone will be, guess what, VOIP within a few years... link here http://www.theregister.co.uk/2004/06/09/bt_ip_net
Slashdot is rapidly declining to the point where Pissy World (UK) / Fry's (US) sales staff will start calling what THEY percieve as stupid clueless customers as "slashdotters" as a term of generic abuse.
"News for Nerds" ??? Give me a fucking break, Twaddle for Teletubbies is more accurate a decription of the content lately.
http://slashdot.org/~GuyFawkes/journal
urk, what a concept.
couple it with the ability to pick up subvocal sounds from sensors near your voicebox and we'll end up like the Belcerebon people of Kakrafoon (HHGGTG reference)
As if the plagues of mobile phones aren't enough (people talking in restaurants, cinemas, while driving), freed from Telco mobile charges it could become a real social concern if it isn't DOA but merely pining for the fjords.
HHGGTG quote: The Belcerebon people of Kakrafoon used to cause great resentment and insecurity among neighboring races by being one of the most enlightened, accomplished and, above all, quiet civilizations in the Galaxy.
As a punishment for this behavior, which was held to be offensively self-righteous and provocative, a Galactic Tribunal inflicted on them that most cruel of all social diseases, telepathy. Consequently, in order to prevent themselves broadcasting every slightest thought that crosses their minds to everyone within a five-mile radius, they now have to talk very loudly and continuously about the weather, their little aches and pains, the match this afternoon and what a noisy place Kakrafoon has suddenly become.
At our Uni, we have 6 campuses over the eastern seaboard of Australia (over 4000km apart). I work in the Infrastructure team and we have been running VOIP since 2000. We are all using AARNET for WLAN traffic and VOIP works wonderfully (CISCO callmanager, CISCO 7960's phones and CISCO infrastructure). Any non-campus (other than Australia University traffic) phone calls (local or interstate calls) hop off at the nearest local AARNET node onto the old analog exchange to the phone number you are calling. This gives us local phone calls all over Australia! The reason it works so well is that AARNET has QOS. In the US, this is a problem and VOIP will never work as well. We are also starting to use Video over IP using the same network. About the only problems we have had is worms and viruses in the AARNET network, but we have blocks into the network and at campus boarder routers that stop this kind of thing happening (most of the time).
Yes QoS defintiely can fix issues like this. Didn't most of us read about Robert X Cringely's idea to make WISP/VOIP providers with WRT54G's??
Gorkman
First of all, full disclosure: I work at Avaya, for their security practice. What I'm about to say may seem pretty self-serving for the company, but I can only hope my posting history establishes me as some sort of credible source.
Second warning -- I'm actually raving about my own company's gear here. I'm way more likely to get in trouble over this, but heh -- can't let an entire nascent industry get tarred over a temporary generation of *ahem* lesser performing equipment.
So, warnings aside -- I was at Hivercon last year. Hivercon's a fun show, set in the middle of Dublin, Ireland (which, btw, is a fantastic city.) I'm sitting there, on:
1) My laptop
2) Wireless
2.1)HOTEL wireless
3) VPN (IPSec w/ 50% packet overhead!)
4) An international link
5) VoIP into a conference call
By all rights, the quality should have been awful. I mean, it had every right to be...
Now, we have VoIP at home too -- Vonage, to be specific. Our Vonage link runs over an 1.5mbit SDSL line provided by Speakeasy/COVAD, is QoS'd at our firewall, and connects directly to our home telephone wiring.
The quality on the international, wireless, IPSec'd, laptop'd conference call through my Avaya softphone exceeded what I was used to from our home VoIP provider. It was basically landline equivalent -- yes, it was even better than my cell phone.
I was _shocked_. I remember PowWow, FreeSpeak, and all those other systems that ran VoIP over Modem lines. In what alternate universe did VoIP become a quality leader under difficult network conditions?
Turns out that implementation matters. I went and harassed some of the people who worked on the phone equipment (heh Brian) and asked how this system could possibly be working at all. Apparently Avaya got a bunch of the people from Bell Labs (it came from Lucent, which came from AT&T, which itself came from Ma Bell), so there was all this knowledge lying around already in how to manage reliable communications like lives depended on it. The big things being used were:
1) Error Concealment
2) Dynamic Jitter Buffers
Error concealment is simple -- there's necessarily 50 packets per second on a 20ms-latency link (1000ms / 50 packets per second = 20ms of audio per packet), and speech is massively redundant. So rather than simply dropping out when packets were missing, the voice client was "filling in the gaps" with neighboring content. Since the overall frequency profile was kept relatively consistent, short term drops were kept outside the range of human perception. Neat -- obvious, and not entirely unique to this particularly implementation (there's direct support for concealment in some of the G.72x codecs), but neat.
The dynamic jitter buffers are cooler. The basic idea here is that some links are high quality and others are less so, and sometimes the quality of the link will change in the middle of a call. As a response, the Avaya architecture will negotiate a longer buffer for packets to be stored before they're output to the listener to be heard. This buffer starts at ~10ms and can scale up to ~300ms -- distracting, but users have been accustomed to higher latency through their love of cell phones (sad, but true). The key is that the human auditory system can't easily detect speed changes at subsecond resolutions, so you simply execute a non-pitch-shifting slowdown of output speech over a second or two and now you've got a jitter buffer far more tolerant of inclement network conditions. Mind you, this is an absolute nightmare for automated testing equipment, which expects time to be constant, but it's great for everything else -- even TTY's! You'd think a 150bps modem could travel over any link, but apparently not...
Anyway, we keep hearing about how Motorola and Avaya are putting out some kind of VoIP phone, so I'm actually pretty hopeful that we'll see a GOOD VoIP/WiFi solution sometime in my lifetime. I can say this much, though -- simply spurting ulaw on the wire and calling it VoIP ain't my idea of a good time.
--Dan
"The future is mesh networking"
The distant future.. maybe. I don't see networking moving over to mesh topologies anytime soon, even if your company has some working systems.
- It's not the Macs I hate. It's Digg users. -
VoIP over WiFi isn't dead... it's aborted before it's even born.
There is no point. There's enough room on the 900mHz and 5.8gHz bands for classic circuit-switched wireless phones to work. If you want better sound quality, you can go digital over that link... but there's no reason to bring along all of the overhead of UDP/IP and WiFi on the exchange. It's better to use a much simpler system of ones and zeros with a basic bit-flipping encryption key.
There's just no benefit to VoIP over WiFi when instead of going over the WiFi bridge you could use a standard consumer 900mHz phone instead.
Furthermore, there's no possible way to order all of the other devices that are causing conflicts on 802.11x to shut up... there's no promise that the interfering device is even part of your network! In fact, there's no promise that the competiting device is even a WiFi device.
IP is nothiing but extra overhead that really isn't needed over a "last inch" network hop.
I have to agree. There are too many variables that could have been wrong.
:) I'd be more willing to declare Amiga dead, but there's hardcore Amiga lovers still using it who may argue with me.
Did he have a weak signal? Was he 300 feet from the AP or 2 feet? Did he have poor signal quality? Maybe he was standing by a wall where someone was running a microwave in the next room. We found a brand new radio in one office was interfering with our 2.4Ghz telephones. It was putting off a *LOT* of noise, even when it was turned "off" but plugged in. There's one room in my house, even though it shows 90% link quality, 802.11b devices suffer performance problems. Every other room is fine.
Maybe it was the throughput of his Internet connection. Was he sharing bandwidth on a 56K dialup, or a poor quality provider? Maybe there was any number of problems between point A and point B. Maybe it was simply the device(s) he was using were faulty. Nah, no one gets bad hardware.
Saying VoIP over WiFi is dead is like saying the Internet is dead because you're on a noisy line and it takes 5 minutes to view a single web page. By this judgement, television is dead, because as a kid I saw more snow on the screen than picture. Was it television technology at fault? No, it's because I was 100 miles from the nearest broadcast tower.
But hey, people declare perfectly viable projects dead all the time. *BSD is dead, right?
Serious? Seriousness is well above my pay grade.
I agree with other posters that one conference failure does not a funeral make. Slashdot gets enough traffic without having to sensationalize everything.
However, the current state of WiFi is pretty sorry. Perhaps I am just flustered because of the problems I've had setting up a WiFi network for the first time, but everyone I know who has setup WiFi has had to deal with a whole array of perplexing problems. Without fail, they end up consulting with tech support to get the connection to work. Many router reviews I read on-line detailed mysterious problems and uneven user experiences. On the other hand, connecting Ethernet is practically like plugging power in an outlet nowadays.
I'm not tech-illiterate. I've built every computer I've owned since high school and have run Linux variants on each of them at one point or another. I don't mind some technical complexity, but setup should be easier than it is, and the connection more reliable.
At this point, I could launch into a rant about cell phones as well. CNN had an article today about growing customer complaints with cell providers in the US. In related news, java.net's front page is leading with a blog and associated discussion about how the current speed of software development is going to get the industry in serious trouble.
I think someone should write an article about the death of the IT industry as a whole. Computer-based consumer electronics and software have an amazingly poor degree of reliability, and there appears to be little liability on the part of companies and few channels of recourse for consumers. Well, </bitter>. I'm going off to enjoy my newly configured WiFi.
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In X-Windows the client serves YOU!
Likewise, I gave an interview via iChat AV from Wellington NZ to someplace in California.
... I can only suggest that, well, you're probably right.
However, I would say that iChat and VoIP are actually very different things. The point is (IIRC) that VoIP has to use much shorter frames and more or less *has* to run over H323 to be compatible with other bits of VoIP gear.
To those of you who say "well, to hell with VoIP and POTS numbers and all that, we'll use our modified IM networks and be DAMNED!!"
Dave
I write a blog now, you should be afraid.
Well perhaps in the UK it isn't worth it, but in the US and Canada Vonage is making a big impression. I'm going to spring for my DSL no matter what phone system I use, so that doesn't enter into the price comparison. Once I add the features I want onto the POTS line my monthly bill before long distance is near $40. The basic fee for the POTS line to support the DSL is around $10, add the $25 Vonage fee and I'm at $35.
True it's not much of a savings prior to long distance, but calling the relatives in Canada is much cheaper on Vonage.
At least here VOIP can easily be justified if you want all the bells and whistles on your phone line.
Sig is on vacation
Not unlike most TV shows. If they aren't an instant insane hit within an episode or two, they get canned. I hate this time period. :P
BytesTemplar.com
I regularly use an Avaya softphone (on my laptop) connected to the corporate Avaya phone switch over a Cisco VPN from a consumer grade DSL connection at home. A colleague does this between Vancouver and Calgary. The major contributer to dropout, of which there is very little, is when my colleague runs the IPphone in a VMware guest image.
I don't think this fellow tried very hard. The company I work for just replaced all of our phones in our local office (500+ people) with a VOIP system, including wireless VOIP phones for many. While they had to iron out some issues early on, the system (and more to the point, wireless VOIP via a wireless LAN) is working extremely well. (Unfortunately I don't know the specifics of the system off-hand)
Seems like Mr. Kewney has an alternate agenda, or is just really quick to jump to conclusions.
It means that VOIP WLANS are 2-3 years away, maybe less.
I can do better than that. I regularily talk to my wife in the Philippines on a 43k dialup (I'm on broadband). The results are less than perfect, with her voice cutting out occasionally -- especially when her prepaid ISP is heavily loaded -- but they're much less frustrating than standard long distance. And I get the satisfaction that, well, sure it's crappy sometimes... but at least I'm not getting charged $0.25 per minute for it. It actually works out closer to $0.01 per minute, because of her dialup. And if the connection is decent, we can send stills from the web cam to each other.
I'm hoping to get her onto a better ISP soon. I think if she could get 56k consistently we'd have a lot fewer problems... and probably need less of a buffer (and thus, less delay).
iChat AV rocks. I never thought it would work on 43k dialup.
You'd have to install a whole pile of even more expensive equipment if your phone company wasn't providing all of the necessary switches and other hardware leading up to your home.
I just moved into a new home less than two weeks ago. The house didn't have any telephone service coming into it, so I had to order it from the local telephone company (Bell Canada). Unfortunately, for new homes they'll only setup your service from the curb to an outside wall of your home. You have to do the rest (or pay them quite a bit to have them do it).
Between the cabling, the phone line, the basic 1x9 phone distribution panel, the wall box to contain it, and various bits and pieces of necessary hardware, it's cost nearly $200 CDN in parts. And none of these components has any processing capability -- it's all simple electronics.
Sure it's easy to think of POTS as being easier than VOIP, but that's typically because the telephone company or someone else has done all the work for you, giving you a wall jack as your interface. If the phone company did nothing but give you a cable with access to their network, you'd have to invest a pile of money into the necesary equipment to make that useful.
VOIP may be in the same boat one day. One of my previous employers went all VOIP for a new office of about 2000 employees, and setup a seperate network just for handling the telephone traffic. For those of us using the system, it was as easy as plugging the phone into the jack marked "phone" -- no different than with a POTS phone in any home (but mine. As it happens, the builder appears to have screwed up much of the phone cabling theey roughed in internally, as thus far only 1 in 5 is actually working :P).
Brad BARCLAY
Actually, iChat is much closer to VoIP than you realize. Apple uses industry standard protocols for signaling (SIP) and streaming (RTP). It's pretty much identical to a VoIP phone call.
You may not see a point, but I do. Sure, I can use a standard consumer 900MHz phone at home, but where this technology really shines is in mobile phones.
The idea is: you have a mobile phone that you carry around with you. When you are not in range of WiFi, then you use the normal GSM/CDMA network and pay the normal price for it. But when you are in range of a WiFi network, like at the office, you can switch to VoIP and talk for free (more or less).
It may not be perfect today, but I think it's pretty close, and in a few years it will be obvious.