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VoIP Cell Phones Coming
bp33 writes "Wireless Newsfactor is running a story about how the wireless vendors are climbing over themselves to get Voice-Over-IP cell phones. You might ask "why bother? We already have wireless voice now." But with an open platform for wireless (Symbian, JavaPhone etc), your "voice" (er .. audio) just becomes bits that your programs can manipulate before sending."
Why do we do everything over IP? I mean, honestly, it's a good protocol and all, but it's not perfect for everything. There are already digital wireless phones, and not all of them use IP.
/rant
Why would one want to use an ATM/IP/IPX/IP network when they could just use whatever works best for that application?
I think that everyone out there wants to just use IP so they feel like they've made some sort of "internet device" when really they have just another damn device with an IP. You can always tunnel just the portions that you want over IP rather than forcing EVERY square peg into that round hole.
Great. Just Great. First it was downloadable ring tones. Now it'll be customized voice filters. I can just see the advertisement now:
"your "voice" (er .. audio) just becomes bits that your programs can manipulate before sending."
I can't wait until someone creates a cell-VoIP-phone virus that scrambles your sentences into vulgarities and profanities whenever you try to call your mom.
Maybe it's just me, but I am forsee so many problems with this. With VoIP cell phones, your phone would bascially become another 'computer'-like node on a network. Look at the problems facing computers today.
First, as mentioned a few posts above, it would be simple to add a voice filter to any phone. Download a program into it, and it will manipulate the bits making your voice unrecognizable. While in some cases, this is a plus, with the annonimity of cell phones now, this could be used for all sorts of prank, and malicious phone calls.
Viruses will run rampent(sp)! A simple cell call from one VoIP phone to another could potentially carry a virus embeded into the bits. Answer a phone call, and your phone's screen starts flashing with Devil horns... or an IE logo... Your phone is now dead.
In addition to viruses, 'dialer' type programs could potentially be downloaded to your phone, and used to call other phones to spread. Your think pr0n dialers now are bad, imagine your phone bill coming in only to notice that your have 100 out-of-country calls on it.
These are only a sampling of the problems we could face. DoS phone attacks, worms, everything that attacks a standard computer now could be used against your cell phone, after all, they are all built about bits sent back and forth...
Is this thing on?
"Hey brother Christian with your high and mighty errand / your actions speak so loud I can't hear a word you're saying"
I'd rather have phones that worked really well first. I'm tried of having half of my calls dropped.
"Oh no, 3 horny women and only 2 condoms...Thank god I read slashdot"
Voice uses circuits for a reason -- latency and jitter *must* be controlled or the conversation goes to hell.
There has to be more to wireless VoIP than simply 3G+ data -- it must be able to control the timing of the arrival of packets.
No, you can't buffer it. Voice conversations are realtime interactive. Fat packet sizes don't help, either. There is a limit to how long you can spend processing the data into and out of a packet before you screw up the timing.
They have a LONG way to go before this will be realistic.
Learning HOW to think is more important than learning WHAT to think.
This looks like yet another dumb justification for 3G cell phone technology. If you just want to ship the voice over long distances as IP, there's no reason to do it in the handset. Do it someplace where you have the connection to a fat pipe in place, like the cellular CO.
Voice over IP is an artifact of telecom pricing and history, not a technical advance. Circuit switching and packet switching now cost about the same (and they're likely to both be over ATM at the bottom.) But voice is billed by the minute, while the Internet is typically a low flat rate, and many countries use landline voice to subsidize other stuff.
But cellular has less of that heavily-regulated history. Where's the justification for this?
The obvious answer: convergence.
If everything is over IP, then you can guarantee at least transport level interoperability with everything. That lets you do things like access mapping services or locale aware restraunt guides, etc., without having to gateway the content.
It also gets around the price differential for long distance service, and further commoditizes the pipe providers as just that: pipe provider, rather than toll-booths that bill based on destination.
Back in the DNSEXT (the IETF working group on DNS), there were a lot of cell phone providers who wanted to assign an IP address to every telephone, making it directly addressable from an outside server.
Among other things, this would let them push content to your phone, based on having a phone/IP identity, so that the phone could be contacted directly.
The downside of this is that they are not really planning on forcing the use of IPv6, and the IPv4 address space actually has too little remaining space for there to be the possibility of assigning an IPv4 address to every cellular telephone in existance.
So while convergence is attractive for the cell phone vendors, and the local carriers (neither of which who could care less if the long distance providers continued to make money, other than as flat rate pipe providers), it's unlikely to avoid the issues of having to have a gateway (NAT) device, unless they go IPv6. The current 3G phones in Europe (and the "2.5G" pgones in the U.S. require gateway devices).
FWIW, both Nokia and Ericson engineers were interested in the IP-per-phone idea when the issue came up on the mailing list, so it's likely they will be the first to be pushing the idea in the future.
-- Terry
"CD quality" does not been just having something recorded at 44.1KHz at 16 bits. A $5 rat shack microphone and a sound blaster is not going to get you anywhere near the capabilities of that low (vs. 24/96 or even 24/196) sample rate. Good audio equipment costs some real money. Take a look at this for a good quality entry level audio card. With good audio equipment (pre/pro, speakers), your $5 rat shack microphone recording will sound like utter crap compared to something recorded with this card (and a sennheiser or comparable microphone). Simple playback of normal CDs through this setup will also be an eye opening expierience.
I am wondering, don't they have PDAs now that have sound capability? If so, why not get a PDA running Linux and Gnomemeeting, get wireless 802.11b access, and chat with someone else with the same setup, for free?
Assuming of course that your PDA has sound capability, and you can hook it up to an available wireless high speed net, and the OTHER person has all of this, too. (Or at least, they are sitting by a computer running Gnomemeeting or Netmeeting.)
The PDA can also do a lot more at the same time, besides acting as an internet "cell phone", so really, it potentially gives more bang for the buck, than a cell phone doing VOIP. (Of course, cell phones are also becoming multifunctional.)
I have already talked to friends using a laptop on a hardline (ethernet) connection. Setting it up for wireless voice chat - or even wireless VIDEO chat - is now a cinch. The drawback is a laptop, even a "notebook", is unwieldy due to its size, as a makeshift cell phone. But it has vastly higher capacities for running software concurrently, and storing data, than a PDA, much less a cell phone.
The point is, we 'hackers' should be working to create an infrastructure where we can easily communicate via voice and perhaps even video, over the internet, WITHOUT extra charges (which VOIP inflicts upon you). We can do it - so why don't we?
--- Grow a pair, liberals... stop letting the Republicans bully you!
My SprintPCS phone already has about a quarter second lag time between transmission at my end and reception at the other end, which, for a fast talker like me, is incredibly annoying. I always end up talking over the person at the other end. If that person doesn't realize what is actually happening, they often think I'm being extremely rude.
The delay is caused by the lag for A-D conversion in my handset, added to the D-A conversion and then possibly A-D again and then D-A again if I'm talking to a different digital cell phone user on another network.
Now if something like that were going to be combined with the added, and sometimes horrible latency of VoIP. Oh forget it. Just give me a land line. I'll pay whatever I have to for the luxury of 1880's technology.
You must be confusing "voice over IP" with "crappy free telephone calls over the public internet". Voice over IP in a controlled private network can have strict QoS guarantees on latency, jitter and packet loss. VoIP is actually used by many millions of people, most of them don't even know it.
Cellular networks use voice compression codecs that must accumulate a complete block of samples before compressing and transmitting it. They also use heavy error correction. Both of these factors introduces a very significant latency. If the voice compression blocks, error correction blocks and VoIP packets are all in sync some of these latencies overlap instead of adding up and it may not add any significant additional latency.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
So VoIP needs QoS - this is a well established technology in IP. There are wireline VoIP providers today who use private IP networks (some using QoS based on queuing) and some who actually use the Internet and get good QoS - the latter have to closely monitor achieved QoS and be ready to switch their traffic to another provider, but they claim good QoS and their costs are very low.
For dependable service, network switching is not enough and QoS is probably essential. This is particularly true with 3G where you might be able to choose from the following VoIP-related services, all with different bandwidth/latency requirements:
- simple voice call
- stereo call (listen in to a live concert perhaps?)
- conference call (high QoS)
- multimedia conference (voice, data sharing)
- videoconference
These more flexible IP services are where circuit switching falls down.
IP QoS will have to develop hugely to work for wireless, though. In wireline environments, you can set up a QoS session using RSVP and have it stay up for minutes or hours, so setup latency is not a big issue. In wireless, the caller could be moving between cells in a car or train, and might spend only a matter of seconds in each cell - every time they move to a new cell, their QoS session must be partially recreated (from the core network to the new cell), in a matter of tens of milliseconds.
For quite some time, it may be more cost-effective to overbuild networks and introduce simplifying constraints, but eventually wireless IP QoS should take off as an invisible support for wireless VoIP and multimedia over IP.
UMTS, a key 3G standard mostly used outside North America, will be All-IP in Release 5, which is nearing completion and should be rolled out in a few years. This mandates the use of VoIP for all use of the IP Multimedia Subsystem (which enables the advanced services listed above). Current UMTS rollouts are using Release 99 or Release 4 (formerly Release 2000), which are much less IP-based.