Updates on VoLTE - secondary not primary voice?

Unlike my criticisms of RCS (which I think was a lousy idea to begin with), I've always been broadly positive about the concept of VoLTE and its predecessor OneVoice. Indeed, I wrote a report in 2007 saying that operators urgently needed to develop a standardised form of basic VoIP telephony for 3G/4G networks.

However, that was 2007. The year the iPhone launched. VoLTE development is now running 4-5 years late, and the mobile world has moved quickly in that period.

A central theme of the report was that operators needed to "practice" with VoIP with HSPA networks in 2008-9, before being forced into using it with LTE. I argued that deploying a new voice technology, on a new network, with all the inter-dependencies and complexities involved, would be too difficult. Understanding the vagaries of mobile VoIP quality needed to be done without the distractions of simultaneously learning how to optimise the radio network itself. 

VoIP quality is a completely different ballgame to circuit voice - even on a well-managed ethernet corporate LAN, let alone a brand new wireless network. It fails in different ways (glitches and so on), has lots of on-device requirements in terms of UI and acoustics, and various challenges with interconnect, service assurance and maintenance. It also needs a way to hand off calls to/from 2G and 3G networks reliably.

One of my suggestions was that operators could use VoIPo3G for assorted less-demanding "secondary" forms of voice service, while leaving "primary telephony" on circuit-switched networks until they'd learned the tricks of the VoIP trade.

It looks like I was right. Verizon Wireless has long been at the vanguard of VoLTE development and testing. In February 2011 it indicated a mid-2011 for VoLTE. Subsequently - and to my complete lack of surprise - it has been pushing back the date. I've heard from various private sources that my assertion that VoLTE would be "harder than it looks" is  right. 

The VZW CTO has now been quoted as saying that the company is "not rushing it", and that full (primary telephony) VoLTE is probably going to be late-2013 / early 2014. Interestingly, in the meantime it looks like they might instead go for the "secondary voice" option, bundling some form of VoIP (and I guess maybe video) into a new communications client along with US-flavoured RCS.

If that happens as planned, it's a very interesting move, because:

1. It's a proper admission that mobile VoIP is *hard* to get right. That's good because it means the scale of the problem has now sunk in.
2. It means operators will have a stake in the "secondary voice" game, perhaps meaning that they now realise voice is about "more than telephony". It will be interesting to see if the new voice apps come with developer APIs, different user "journeys" such as call-invitation rather than interruption and so forth
3. It means that operators will be prepared to admit to users that having 2+ voice apps on one device can work, and that "ubiquity" isn't necessary. Most users know this already if they've got Siri or Skype or Viber, but it's quite something to see confirmation from the Establishment.
4. There seems to be recognition that the world is not standing still waiting for VoLTE to be ready for prime-time. Every month's delay is a month that Skype and its dozens of rivals get better at running 3rd-party voice apps over 3G/4G networks - and a month in which users get habituated to them. Therefore operators either need to do "something" with beta-grade VoLTE, or go down an alternative OTT-style route.
5. It looks like the operators - in the US at least - will try to stick to a "federated" model for mobile VoIP rather than doing a #TelcoOTT . Although maybe some will follow Telefonica's lead and back both horses.

The last two points are worth revisiting. The idea of "hedging" is one that seems to be taking hold in telecom operators. I had senior representatives of both  Deutsche Telekom and FT/Orange on my panel "Operators vs. OTT" session at the Open Mobile conference the other day. Both suggested that it "wasn't a black and white situation" and that there was scope for various forms of grey in partnerships, Telco-OTT services and so on. I'd goaded them a bit with Telefonica's recent bold moves with TU Me and other services, and the response surprised and impressed me. They're prepared to try multiple options for voice and messaging, probably targetted at different customer segments.

My question is whether operators have the management and governance (and resources) to back multiple horses - and also whether they can still say "It's just there, it will be ubiquitous" while simultaneously planning another option if it isn't. I'm not sure if anyone has ever devised a version of the Prisoner's Dilemma in which the inmate tells different stories to two different prison guards, but that's what this sounds like. If any game-theorists would like to comment, I'd be very interested.

There are also some interesting challenges if we have VoLTE for secondary voice - such as how it interacts with the primary voice user experience. Which takes priority for incoming calls? Do both feed into the same call register? Do you have a number (and if so is it the same?). Does it work over WiFi? It'll be very interesting to see how that UI is managed, especially if there are also 3rd or 4th voice apps on the device from someone else.

I also had  another Open Mobile session on 4G, with  an EVP from Tele2 and the CEO of Everything Everywhere, while the head of mobility at Teliasonera had a keynote. None of them sounded particularly excited by the imminent arrival of VoLTE either, expecting it vaguely "next year". A common theme seemed to be that circuit-switched fallback "should" be good enough, although there's a conspicuous lack of data about uptake or user-satisfaction for CSFB.

Fitting all this together with a comment I'd seen in a GSMA presentation a few months ago - that VoLTE would be "massmarket" in 2014 - and an interesting picture emerges. We're about to have at least two years where mobile operators are going to be forced to do interesting things with voice, because primary-telephony VoIP isn't ready yet.

The one operator that leaves in the cold is probably MetroPCS, which seems to have been banking on VoLTE being mature this year, and which is probably in greatest need for it as it has capacity headaches for circuit. It will also be interesting to watch what the Asian LTE operators do - my guess is stick with CSFB or perhaps revisit the dual-radio idea already seen on CDMA/LTE phones.

Lastly, I've seen a couple of things about VoIP on HSPA (notably from Qualcomm), but that seems to be positioned as a follow-on to VoLTE, allowing use of full mobile VoIP in areas with no 4G coverage, without the extra horribleness of SR-VCC handovers to circuit.