10 things to know about VoLTE and VoWifi not working (or why 112 may cease to function soon)

Rudolf Van Der Berg
5 min readAug 16, 2021


Last week I asked this question on Linkedin.

Does anyone know how telcos certify mobile devices? VoLTE and VoWiFi have been standardized for a few years now, yet it is hit and miss whether a new phone will have this activated. What is this gap between standard and implementation? I have some phones on KPN where a Samsung A02 and an Android One Nokia G20 will work, but Pixel 4a and Moto G pro who are also Android One won’t. Carrier websites are notoriously out of date and inconclusive, with phones that aren’t listed that work, but phones that are listed not working because of ..?gremlins? https://www.linkedin.com/posts/rudolfvanderberg_does-anyone-know-how-telcos-certify-mobile-activity-6831172450282221568-ZoSr

The response has been a stunning thread so far: I received excellent input from: Arjan van der Oest, Richard Marijs, Raymond Bouwman and Alain Fiocco. We could do with input from handset makers, Android developers, regulators etc.

To paraphrase the debate:

VoLTE and VoWiFi is a mess and it needs (the threat of) regulators to sort it out

and to add, now that 2G and 3G circuit switched voice is meeting its end of life on mobile networks, this might well mean that many phones won’t be able to call 112 in a few years.

The reason VoLTE and VoWifi often don’t work is (my paraphrasing and opinions):

1. it isn’t (just) telcos who play a role in determining whether a user can use VoLTE and VoWifi. Yes they have to test, so there may be bottlenecks there, but it isn’t just them not willing to work together. (My working hypothesis was to blame telcos),

2. it’s the handset makers (Apple, Samsung, Nokia, Motorola) who should install and configure settings and whitelist telcos and MVNO’s but often can’t be bothered. Apple is a well known bad boy also for eSIM integration (hadn’t thought they were so reluctant to get stuff working),

3. The System on a Chip vendors (Qualcomm, Mediatek etc.) often deliver the settings with their chip and the smaller vendors just use that list, forgetting and omitting MVNOs or anybody else

4. Operating systems don’t play a big enough role MVNOs and Telcos can register their APN data in the Android Open Source Project, but it’s a crapshoot whether it will end up in a device. This doesn’t appear to be the necessary data for VoWifi or VoLTE, but it shows that just registering data at a location isn’t enough.

5. the GSMA (A mobile telco lobby organisation who don’t allow MVNO’s to be a member), maintain the NSX database with operator settings including for VoLTE and VoWiFi, which handset makers could use but don’t. Apple and Samsung flat out refuse. Because they can’t be bothered. MVNO’s appear to be excluded. (A lobby club guarding the implementation of standards doesn’t seem right)

6. Network platform vendors have conflicting interpretations of standards. The VoLTE and VoWifi implementations of network vendors appear to be not fully standardized either, so this may cause implementation issues. Your phone may work with an Ericsson network, but not with a Huawei or Nokia network.

7. the 3GPP was only mentioned as the organisation that chose the wrong VoLTE implementation (out of six proposals?) Other than that the 3GPP appears to play no role here.. (Weird in my opinion that we have a global standard, that no one agrees on, rough consensus and running code is not a thing here it seems.) The story I heard was that everybody kind of forgot to standardize VoLTE, because they thought another 3GPP working group would do it. But you know, that is just as good as 6 ideas and the wrong one chosen.

8. Regulators aren’t involved (enough). It used to be that a GSM phone could make a call anywhere. For Europe this was the whole idea behind the Groupe Speciale Mobile in the eighties; interoperability. That is dead now and regulators aren’t involved in making sure it is true for VoLTE and other mobile communication standards, such as eSIMs. (Maybe someone at the European Commission or Berec should have a look?)

9. Telephony is old and done the way it was developed in the eighties. Traditional switched 2G/3G voice is to be phased out. There is no guarantee the industry will fix its problems and this means there is no guarantee consumers will be able to call 112/911 and other E.164 telephone number based services in the future. There is no guarantee an off the shelf phone will work with VoLTE or VoWiFi. The result will be that consumers will use Whatsapp Voice and others even more for personal calls, but it will leave governments and businesses with a huge gap in their connectivity strategy

10. Competition is in no one’s interest. The lack of standardization and implementation hurts competition in the market. MVNO’s, smaller niche handset makers, M2M-providers all appear to be facing a threat from larger manufacturers, SoC-providers and MNOs, who all are under no obligation to make things work. Only if you control millions of subscriptions and your CEO can make a credible threat to the bottom line of a sales dude at Apple, Samsung, Ericsson, Nokia or Vodafone, KPN and T-Mobile, can you get something to work.


It doesn’t really hurt anybody important’s bottom line too much that VoLTE and VoWiFi don’t work. It saves work for handset vendors, SoC vendors, mobile network operators, network gear manufacturers etc. The pain is with MVNOs, consumers, smaller niche manufacturers who have no guarantee they can get their products and money to work. This is a typical situation for a regulator to step in and hand out detention to the bullies in the class. (Or for an industry to realise that it needs to sort itself out, before the adults come in and start making stuff complicated.)

If you want to discuss privately, send me a message on Linkedin, or an email at rudolf.vanderberg@stratix.nl or call using tel:+31630913213 in one of your favorite communication applications as an identifier (maybe I use it too).



Rudolf Van Der Berg

Accomplished management consultant with 20 years of experience in Internet, telecom, privacy, online content, standardisation and peripheral topics.