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US Wireless Carriers Shifting To Voice Over LTE
jfruh writes "For years for cell phone companies, one specific kind of data — voice calls placed by dialing a traditional telephone number — was entirely different from all the other kinds of data a phone used. But in the U.S., that's finally starting to change, as all the major carriers are planning shifts to voice over LTE. The carriers promise sharper call quality and quicker connections."
Or will it be counted per minute? Per byte sounds more reasonable.
Blindingly obvious to me is the fact that voice calls and SMS reaches me even without a high bandwidth 3G or faster data connection. If this leads to better network coverage for high speed data, I will be the first to celebrate, but until then I will stick to a split data/voice provider ... or one that can transition relatively seamlessly between the two types of networks...
Cheers!
Atheist: Buddhist in a Prius
From the article: "For VoLTE to work, both phones on the call need to have the software." So it doesn't work by having the network act as a proxy between the old GSM voice protocol and the new VoLTE protocol. Will it work even if both VoLTE-supporting phones are on different carriers, or will calls between AT&T and T-Mobile need to fall back to old tech?
until [data coverage improves] I will stick to a split data/voice provider ... or one that can transition relatively seamlessly between the two types of networks
The article mentions that T-Mobile will implement handoff from VoLTE to the legacy system. "T-Mobile is using eSRVCC (Enhanced Single Radio Voice Call Continuity), a feature from the LTE Advanced set of standards, CTO Neville Ray wrote in a blog post. The new feature will ensure calls don't get dropped when users move into areas that don't have LTE, he said."
Wouldn't this make it obvious that voice/data are interchangeable and limiting one would be silly?
First, data doesn't get the same protections as voice. Not that voice gets much protection as it is.
Second, carriers have said they will throttle data connections. This has serious implications for digital because it means carrier-to-carrier connections will (not may, will) be of inferior quality.
Third, I would believe digital was going to deliver, except that nobody uses much in the way of error-correction, the speakers and microphones are deteriorating in quality and reliability is naff.
Lastly, phone companies always promise jam tomorrow, or an increase in chocolate rations, but the reality is very different. I get a (billed) month of no service because of an upgrade to 4G. I can't remember the last free phone upgrade offered. My smartphone reboots itself regularly for no obvious reason. I used to be able to run a phone on full batteries for 2 days without a recharge. (Yes, phones "do more", but I don't bloody well want most of the more and the bits I do want aren't any bloody good! That is NOT a good exchange for 1/12th the uptime and nobody sells low-consumption phones any more.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
I had a smart phone for years then decided I was tired of paying through the nose for data plans. I've since reverted to a $20 dumb phone on a $7 a month prepaid arrangement. I just use the old smart phone on wifi which is nearly ubiquitous in my regular haunts.
How long until I have to have some sort of smart phone[along with $30-40/mnth data plan] to 'have a cell phone'? I reckon that'll be the day I transition to straight voIP through Vonage, etc.
This must also simplify collection of meta-data for the spokes too.
Once upon a time when 128Kbps BRI ISDN was fast, voice calls were frequently billed at a lower per-minute rate than data calls. To take advantage of this, a common trick was to place a voice call and then pass data over it. This did result in a lower data rate of 56Kbps per channel or 112Kbps overall, but if that was enough, you could save a lot of money.
Fast-forward to VOLTE.
Most wireless carriers offer unlimited voice minute plans. Since it's all going to be IP over LTE now, I have to wonder if there will a way to pass your data off as a 'voice' call and avoid data caps and limits? Not on a stock phone, but on a rooted device with a custom OS build, maybe?
Data, communications, all synonymous, eh? I mean, HTTP really is a back and forth exchange.
Yep, reclassifying all Internet services as Title II makes so much sense.
Remember a time when cellular carriers were trying to justify getting rid of unlimited data plans by claiming that the networks were becoming oversaturated?
Pepperidge Farms remembers. And we'll remember it when it happens again.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
I just use the old smart phone on wifi which is nearly ubiquitous in my regular haunts.
But how ubiquitous is Wi-Fi between haunts, such as while riding transit?
Comment removed based on user account deletion
I must decline your offer because AOL back in the early 1990s with a 2400 bps modem was 1000 times cheaper than that, at $0.01 per kilobyte.
What I learned over the years is that I don't need to be constantly plugged into the Matrix. It is actually better for my productivity
Until the applications that you need to use stop offering a useful offline mode in favor of increased reliance on "the cloud" (that is, someone else's computer). "Please connect to the Internet to save your changes." Or "Please connect to the Internet to identify this song" (as opposed to recording the snippet while it is playing and identifying it once you do connect; Google Play Song Search is guilty).
So, now your voice calls impact your data caps?
Sometimes, real fast is almost as good as real-time.
You're forgetting iPV6 has protections for VoIP as well as added other beneffits. As more carriers make the switch its reasonable to assume everyone will just use this down the road
GSM phones will not talk to VoLTE phone with the current LTE revisions. A T-Mobile VoLTE phone cannot talk to an AT&T VoLTE phone (unless roaming- the latency requirements are too rigid to allow for it).
The main driver behind VoLTE is to get more traffic over to one type of network (4G) instead of having to keep two networks up and running (4G+3G).
So unless all major carriers merge into one, something that no sane national competition regulator will approve, all carriers will have to keep their 3G networks going more or less indefinitely. These limits would appear to prevent any substantial progress toward the "main driver". And good luck replacing the CDMA2000 flip phones that people still use precisely because voice-only service on a dumbphone is cheaper than voice and data service on a smartphone.
Why do you want error correction of any sort for an audio stream?
Ask the inventors of Compact Disc Digital Audio why it includes CIRC error correction. I've had too many calls stay in the loss concealment zone to the point where unconcealed losses keep me from understanding the other party.
Error correction introduces latency
I don't see why it'd introduce more than 10 milliseconds.
Let's see - drop the voice connections. Decreased operations cost for the provider. Don't pass the cost reduction to the customer. SCORE! Use more bandwidth, making people either go over data caps and get penalized or have to buy larger data allowances and pay more for service. SCORE AGAIN! Tell them how awesome the new service is, when the old service worked and sounded just fine, making you look like a hero for screwing them over. TRIPLE SCORE! Use the extra income to build out your network! Oh, wait. No. Can't do that - daddy needs a new Bentley.
"The carriers promise sharper call quality"
As someone who started in cellular field in the late 1980s, I'd say it can't get much worse.
You can still do MOU (minutes only use) billing for data for CDMA / Verizon wireless.
Truely unlimited minutes:
Even the slowest 1xRTT could get you ~15-45GB/month
With a realistic 5K "unlimited" minutes cap (~3hrs/day):
1xRTT = ~ 200MB/month.
1xEVDOrA = ~1.5GB/month
All you have to have is the correct billing code added to your account.
Losing one packet out of 50 in a second can be concealed, I understand. Even CD players predict waveforms for blocks where CIRC fails. Losing ten packets is harder to conceal, as far as I know. I was just guessing that if packets can be corrected instead of lost, fewer losses will be presented to the loss concealment layer. I was thinking about adding some forward error correction (FEC) to each packet so that enough correctable packets make it across the channel to give loss concealment enough data to work with. I know TCP-style retransmissions add unacceptable latency, but what latency does FEC add? Is it an algorithmic latency (like lookahead in an audio codec) or just a practical processing latency? Or are losses in practice already beyond FEC's ability to correct?
dude reading that paragraph hurt my eyes and my brain...
please either copy an excerpt or learn how to write.
thank you
I wonder if this means that my calls will drop any time I switch from one cell tower to another while moving at highway speeds, much like my Sirius app seems to do ever since 4g was rolled out with my carrier.
I don't know the VoLTE protocols, but for regular PBX-style VOIP, the voice compression is good enough and the voice payload in the packets is small enough that most of the bandwidth is used for IP/UDP/RDP headers, not the actual voice. There are way too many standards to choose from, but most of them run about 5KB/sec or less (that's bytes, not bits), so about 300 KB/min, or about 3000 min for 1 GB. There are people who use that much voice time, but not many :-) I'd expect that for a while you'll see multiple different standards for handling hd-mobile-to-hd-mobile, sd-mobile-to-sd-mobile, mobile-to-wireline, mobile-to-other-mobile-carrier, etc.
Back around 1990, I went to a technology talk by a guy from MCI who thought that the conflicting economics of offering voice and video on the same network were going to be a serious problem for telcos - video at the time meant ~1.5-3 Mbps corporate teleconferencing, and either you could price video too high to sell much of it, or you could sell T1 bandwidth cheaply enough to make videoconferencing affordable, in which case you'd undercut your voice pricing because companies would buy your video T1s to interconnect their PBXs for cheap. Better video compression got us out of that hole for a few years (384kbps or especially 128kbps video didn't cause that much trouble), but the Internet came along and started doing the same technological undercutting, VOIP started becoming feasible, etc. Mobile phones gave us a way to charge lots of money per minute again, but Moore's Law is still relentless.
Disclaimer: I do work for AT&T, but I do computer security, not mobile phones, so I have no idea what they're planning to charge for this, this is my own opinion, not the company's, blah blah blah. On the other hand, I have been doing various kinds of telco things for many generations of technology :-)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
My GPS uses 2G cellular to get its traffic data and gas prices and to do Google search for destinations. It's going away next year, because Garmin's contract with the cellphone carrier isn't going to be renewed :-(.
Carriers really want that spectrum back, and 3G and LTE are much more efficient in terms of data bitrate per MHz of radio, plus they want to cut down on the number of separate types of equipment (not only for equipment costs, but also because keeping two separate channels of data is much less efficient than one fat channel.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Vanilla telco G.711 is 64kbps, and it's what the digital parts of a telco voice call use. G.729 codecs, mostly used for PBXs, use 8 kbps. GSM had several codecs, including 13.3, 6.5, and less. The problem with all of these is that they need to send lots of packets per second to minimize latency - typically 20 or 30 - so the transport protocol overhead is usually several times higher than the actual voice payload, between IP, UDP, RDP, plus any layer-2 overhead (Ethernet's huge, or ATM's a bit less, if your DSL is using ATM.) In some limited environments there are ways around it, e.g. using CSLIP to do header compression on modems or whatever, but I don't know if most of the LTE carriers are going to do anything like that, or if they're just going to run native VOIP.
The overhead gets a lot worse if you need crypto and implement it naively using IPSEC, because you end up with a couple more layers of headers on top. It would obviously be better to have an encrypted payload standard, because then all it would cost you is some setup key exchange, but the telcos haven't had a big reason to do that, and most of the IP PBX vendors haven't either.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Jitterbug's been a great phone for my mom. Her vision's not very good, so she doesn't bother texting (she'd need to hold a magnifying glass in one hand and use the phone with the other) , and she's stubborn enough she doesn't like to carry the phone around unless she expects to need it (e.g. going somewhere that she'll need to call a taxi), but it's reliable, does voice just fine, has big buttons for dialing, and makes free long-distance calls (so she doesn't bother buying long-distance from her landline telco any more.) The only way a smartphone would do her any good would be if Siri or equivalent could do everything, not just almost everything.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
When you make a VOIP connection, you're signalling to the network that you want to do that, it finds you the IP address and port number, either for a gateway into the old telco network or else for the phone you're calling. That's not getting you out to the public internet, though if you've got another friend with another rooted phone who's also got an active wifi connection, maybe you could do something useful with it.
But remember the other signalling that's going on, between your phone and the cell tower, which is keeping track of how much bandwidth you're sending - you'll have to make it think you're on a voice call also, if the voice prices are managed separately from the data prices.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Back in the 90s and early 2000s, we were trying to sell businesses on using 8kbps G.729 calls from IP PBXs instead of 64kbps telco voice, and they would whine about Mean Opinion Scores and latency (and didn't get that India just wasn't going to get any closer and the speed of light wasn't going to change.) Cell phones convinced most of those people that they didn't really need to care - GSM was 13kbps or 6.5, and your office PBX phones had much better microphones than a typical cellphone and usually didn't have wind noise and trucks going by in the background.
I did have one friend who kept an analog cell phone around for a long time after most people had switched over to digital, because he spent a lot of time out in the mountains and back-country where there wasn't yet much cellphone signal, and a bad analog call was noisy, while a bad digital call just wouldn't stay connected.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
VoLTE IMS voice uses a dedicated low latency guaranteed bearer for the RTP packets. Traffic on this bearer is charged separately and is not routable to regular Internet.
The SIP signaling also uses a dedicated AP that cannot be used for anything else. Traffic is only allowed towards P-CSCF.
All the IMS client, Quality of Service and dedicated bearers are implemented in the baseband chip (Qualcom dominates that market) and is off-limits to the operating system of the phone, even to root.
Which has no measurable LTE. But I'm sure they'll tell us they're 'upgrading the towers in your area' for the next 20 years.
T-Mobile is already doing a variant of this. They recently pitched to the company I work for and it was a topic that came up in conversation. They apparently support voice and SMS over IP, so while they're not doing it over LTE, if you've got poor cellular coverage but have WiFi you can use that WiFi to make calls and send SMS texts transparently. It's only supported on Android devices because Apple doesn't want to support it for only one carrier (T-Mobile's explanation).
Personally, I'd like to see more carriers start doing things this way just from an end user experience perspective. T-Mobile has absolutely horrid coverage at both my home and office but at both places I have good Internet service so I can still use the phone normally.