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."

Comments

Seamless fallback

[vigmeister]

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!

Does VoLTE work from one carrier to another?

[tepples]

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?

Re:Does VoLTE work from one carrier to another?

[profplump]

It doesn't. They can terminate the VoIP call to the PSTN. It's just that when they control both ends it's possible for the devices to talk directly to each other, using whatever route the IP network finds most efficient, rather than forcing all calls out onto the PSTN or through their central VoIP server.

It's nothing different than the way SIP calling works today in non-mobile contexts -- all setup goes through a central server, and the server *can* route to non-SIP targets or forward voice traffic between SIP targets that can't reach each other, but it's *also* possible to bypass the server for voice data if the endpoints can reach each other directly and speak the same language.

Re:Does VoLTE work from one carrier to another?

[schnell]

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

Kinda sorta correct but only in a very narrow sense of "talk to." True, you can't currently roam across VoLTE carriers - which is why all these phones will still carry 3G chips for a long time to come. HOWEVER, when you make a VoLTE call, the carrier routes it back to their PSTN switches, and where it goes from there is immaterial - to a land line, to another carrier, to a data-less feature phone, wherever. So it's not like having a VoLTE phone means you can only call other VoLTE users on the same carrier - you can call whomever you want, wherever. It's just the VoLTE capability itself on that phone that is restricted to where you can use it.

Re:Will it count against the data?

[Bradmont]

Will it count against the data, or will it be counted per minute? Per byte sounds more reasonable.

Do you have any doubt that it will be counted as both?

Yep, they're doing seamless feedback

[tepples]

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."

Re:Yep, they're doing seamless feedback

[KeithJM]

They won't want to pay for both systems forever though. The reason you'd do something like is partly to make your customers happy, but partly because you realize you're installing two sets of hardware on each tower (one for data, one for telephone calls) and if you treated everything like data, you could save money on purchasing and maintaining the hardware because you'd only need to install one.

Re:Yep, they're doing seamless feedback

[omnichad]

And eventually you could use both frequencies you control for LTE, leading to much higher capacity.

Expose limits as unnecessary?

[ReekRend]

Wouldn't this make it obvious that voice/data are interchangeable and limiting one would be silly?

Re:Expose limits as unnecessary?

[timeOday]

What makes them different is time-sensitivity. Voice packets can't be delayed, even for a quarter-second, without making talking really annoying. Sure voice packets should still use the same protocol, but they need higher priority, and you would expect to pay less for lower priority stuff that isn't interactive - even streaming video can easily be buffered for a half-second to mask jitter.

Re:Will it count against the data?

[alen]

everyone offers unlimited minutes these days

Re:Will it count against the data?

[BronsCon]

This. Sadly, AT&T and Verizon will definitely do this. I don't doubt that T-Mobile will, as well, but since they offer unlimited (albeit, there's a cap on LTE speeds and you get throttled back to 2G speeds when you hit it -- unless you pay $30/mo for unlimited, which I do) it won't be quite as much of a cash grab for them. Sprint is an entirely different situation, being unlimited, but not really having enough data capacity to support it...

ISDN flashback

[BaronM]

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?

Re:Will it count against the data?

[ganjadude]

probably. I currently have verizon, and I get unlimited calls and text, but limited data (family plan that im not in charge of, verizon talked my dad into "upgrading" IE losing unlimited data) I can see verizon counting the call data as data and still insisting that you have unlimited calling

Re:Will it count against the data?

[Shakrai]

Do you have any doubt that it will be counted as both?

Stop with the FUD. Verizon doesn't double dip for MMS (picture messages use data, but they do not add to your data usage), even though such double dipping would likely go unnoticed, why would they do it for minutes?

There's plenty of legitimate things to bash the cellular carriers for without making shit up.

Re:Some problems

[interkin3tic]

My smartphone reboots itself regularly for no obvious reason.

That's probably not AT&T or verizon's fault though.

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.)

Well then go back to a dumb phone. 38 days of battery life on the nokia 515. Or buy an expanded battery. Plus, again, how is that your carrier's fault?

I can't remember the last free phone upgrade offered.

Did phone companies ever offer you a phone that was worth more than $20 without a contract?

The first part of your post makes sense I think but asking AT&T to give you a free portable computer that has no software problems and doesn't occasionally need energy is a bit unrealistic.

Re:Will it count against the data?

[Anonymous Coward]

Why would they do it for minutes?

As an experience and abused Verizon subscriber, I would offer several reasons.

(A) The can
(B) They want to
(C) They are Verizon
(D) All of the above

My guess is D.

A new way to screw your customers! Nice!

[MikeLip]

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.

Re:Will it count against the data?

[DigiShaman]

I have a shared 3GB month data cap (family plan), but unlimited voice with Verizon. Are you saying that by virtue of making this change, my contract is by default null-and-void?! Wow, I'd love to see the backlash from that hammer!!!

Re:AOL

[omnichad]

But Verizon beats that at .002 CENTS per KB

Voice Doesn't Use Much Data

[billstewart]

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 :-)

Re:Will it count against the data?

[evilviper]

Stop with the FUD. Verizon doesn't double dip for MMS (picture messages use data, but they do not add to your data usage), even though such double dipping would likely go unnoticed, why would they do it for minutes?

Verizon does double-dip in some situations, and has TRIED to do it more, but once the DoJ put their foot on Verizon's neck and started investigating, Verizon changed their mind... Or rather, delayed the changes indefinitely, and eventually rolled them out only slowly to new customers and new devices for a mish-mash of reasoning.