AT&T starts testing cross-carrier VoLTE calls

AT&T starts testing cross-carrier VoLTE calls
In a blog post on Wednesday, AT&T said that it recently completed cross-carrier VoLTE phone calls in select areas. AT&T's goal is to allow its subscribers to enjoy HD Voice audio and video calling when placing an VoLTE call to someone using another carrier. The nation's second largest carrier and T-Mobile are both in the midst of such testing.

AT&T says that its VoLTE signal reaches 96% of its LTE coverage area. That works out to 295 million POPs. With 27 million of its active subscribers eligible to receive the carrier's VoLTE signal, AT&T is ahead of the competition in this department.

Looking back at 2015, AT&T mentioned some of the calling options it is now offering to subscribers. For example, iPhone users with iOS 9 can take advantage of Wi-Fi calling in areas where an AT&T signal is hard to come by. AT&T says that it plans to offer the feature to other operating services (read Android) in the future. The mobile operator started offering the service in October.

Number Sync allows you to send or receive calls and texts sent to your mobile number through other devices, even if your phone is miles away and turned off. The Samsung Gear S2 smartwatch will now support Number Sync. And Advanced Messaging, which works with the Samsung Galaxy S5 mini and Samsung Galaxy S6 Active, allows you to see when a sent text has been received by the recipient. You will also know when the text has been read, and when a reply is being typed up. It also increases the size of files that can be texted to 10MB.

source: AT&T via Engadget



1. mike2959

Posts: 697; Member since: Oct 08, 2011

There goes the data usage. There goes the battery life. Unlike like the average 17 year old on this site people actually talk on the phone.

2. Augustine

Posts: 1043; Member since: Sep 28, 2013

Carriers do not count VOLTE calls towards data, but towards minutes.

4. WillieFDiaz

Posts: 127; Member since: Dec 22, 2010

Battery life over VoLTE is actually increased as it is a SINGLE RADIO capable of not only voice, but data. Contrary to say TWO RADIO devices that use 1 radio for voice and 1 radio for data, where both would be turned on, draining the battery.

7. Augustine

Posts: 1043; Member since: Sep 28, 2013

When placing a call over a GSM network, without VOLTE the radio steps down to 3G for the duration of the call. Both voice and data can share the same one radio on GSM. When placing a call over a CDMA network, without VOLTE the radio changes to 3G for the duration of the call. Because voice and data cannot share the same radio on CDMA, there is no data.

10. JunitoNH

Posts: 1946; Member since: Feb 15, 2012

Mike, I was thinking the same. It may start as a free a service, but eventually it will count towards your data allotment, and we will be back counting minutes. Since everyone is providing unlimited calls and sms, a new strategy had to be employed.

3. WillieFDiaz

Posts: 127; Member since: Dec 22, 2010

Lets get something straight here - T-Mobile has 100% VoLTE on their LTE network, every single area of LTE has VoLTE active, so THEY are ahead of AT&T in this. AT&T was testing cross carrier HD Calls with Verizon, and cross carrier VoLTE calls are not reliant on anything other than the device and network compatible with VoLTE - which more accurately VoLTE is active IF one user has a VoLTE device and is within the LTE network. You dont need both user and devices to be VoLTE compatible or within the same network, in fact, most people are confused, because the HD portion of VoLTE needs this, but to make a standard non-HD call over VoLTE all thats needed is just pick up the phone and make the call over LTE. Simple.

5. o0Exia0o

Posts: 903; Member since: Feb 01, 2013

I think your confusing VoIP (Voice over Internet Protocol) with VoLTE (Voice over LTE). VoLTE is HD calling just renamed by the carriers. In order to make a VoLTE (HD calling) call BOTH devices on the call have to be VoLTE capable. VoIP on the other hand all you need is an internet connection and 2 internet connected devices (eg. computer or Smartphone). AND no T-Mo is also staging their VoLTE rollout like AT&T. Verizon is the only carrier that currently offers VoLTE services everywhere their LTE signal reaches.

8. Augustine

Posts: 1043; Member since: Sep 28, 2013

No, it is not. HD calls simply use a more advanced codec, whether the call is placed over a voice circuit or over VOLTE. The latter does not use a voice circuit, but the packetized LTE network.

6. Omarc07

Posts: 574; Member since: Nov 12, 2012

I think the only reason T-Mobile has more volte than AT&T is because T-Mobile has half the coverage compared to AT&T. AT&T is probably taking longer with volte because it does have a bigger network to cover.

12. SprintGuy26

Posts: 229; Member since: Mar 21, 2011

thats true but if t-mobile has their whole network on VOLTE then t-mobile is done and can now focus on building out their network, there for beating AT&T but yes u are right AT&T does have way more coverage than t-mobile and it will take them a lil longer to get that 100%..

9. mike2959

Posts: 697; Member since: Oct 08, 2011

VoIP an VoLTE is technically the same.

11. Bernoulli

Posts: 4362; Member since: Sep 01, 2012

Um no, go back to whatever you do as a 17+ year old human being.

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