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Thursday, January 27, 2011

I'm picking a fight with a peer, about VoLTE and IMS

It's quite rare for me to take direct pot-shots at other specific analysts. While I'm often confrontational, I try to avoid ad-hominem attacks, or cast doubts on specific items of work.

I'll make an exception in this case, because I know the analyst quite well & have a lot of respect for his other commentary, as well as our banter on Twitter, via blog comments, or over a beer at various conferences.

I reckon Gabriel Brown (@GabeUK) has called it wrongly on VoLTE and IMS in his latest article. I vehemently disagree - based on discussions with operators, vendors and my own analysis - that IMS platforms are likely to become the main long-term platform for telephony or other applications in mobile operators in the long term. IMS will most likely be used patchily, by some operators, for some purposes, in some places. (Note: I haven't read his full report, which the article is a trailer for, so there may be some more contrarian viewpoints contained in it).

I certainly don't see that VoLTE will be the catalyst to "set the stage for a more fundamental transition to operator-provided real-time, rich-media services" - that is more GSMA-style wishful-thinking, rather than a probable outcome. And I completely dispute his assertion that with VoLTE/IMS "investment won't be sunk into interim measures that close off that route to innovation".

What he doesn't discuss is that VoLTE is mis-named. It's actually more correctly called ToLTE - Telephony over LTE, not a generic voice platform. It isn't designed as a ground-up answer to the question "what should voice communications look like in future?". I wrote a report in 2007 saying that there needed to be a 3GPP standard for "plain old mobile telephone" service for IP-based mobile networks, and that it was urgently required to stave off the fast-improving third party VoIP providers. The belated answer is VoLTE, aka ToLTE. It's now 2011 and the expectation is that the majority of 3GPP operators are unlikely to deploy VoLTE commercially until 2013-2014. Which means it won't gain significant uptake among massmarket users until perhaps 2015-2016.

Don't get me wrong, an agreed solution for ToLTE would have been important in 2007-2008, because it would have been ready at the launch of LTE last year.  It could have been a good defensive move, adding in all the legacy baggage around telephony such as "supplementary services", roaming and assorted requirements for regulation and control. But the problem with defensive strategies is that they have a timing window, after which they're useless. A missile defense scheme needs to destroy rockets in the launch phase, before they break into multiple warheads and re-enter. A football defender needs to tackle someone before they run past towards an open goal.

In many, perhaps most, cases for LTE, it now seems clear that defence will be too late by 2014-2016. For all but the fastest and most value-chain controlling operators or countries, several things will have happened by then:

  • A significant proportion of voice application usage will be "non-telephony" by 2015. This is happening already - voice is being embedded in applications and software as a feature, not a service. It might be using a Skype connection as a baby-monitor, or in-game speech between players, or 10,000 other voice use cases. These are not in any sense "phone calls" and are very poor fits with both VoLTE/ToLTE or today's circuit infrastructure.
  • A further substantial amount of the VALUE of both telephony and voice applications generally will have migrated to "cloud voice" by 2015, embedded into websites or business processes, especially for high-end users who will be first to LTE. VoLTE is not designed as being developer-friendly or "mashable" as a #1 goal, which would have been fine in 2007 but not in 2011. (I remember being the chair of an IMS conference on the day that Facebook launched its HTTP-based IM chat. So it's slightly ironic that this debate is happening the day Facebook seems to have trialled its "call" function.)
  • More regulators will have started to allow portability of mobile numbers to third-party VoIP services, and more companies will support it. Google Voice announced it for the US last week. At the moment, mobile number ranges - especially in Europe - are sacrosanct and only available to network owners and their MVNOs. Lets see how long that lasts, and indeed whether numbering retains its psychological importance against other identifiers.
  • The stickiness from SMS, which keeps people from moving to VoIP for primary telephony today, may start to be eroded, especially among LTE users who are likely to have smartphones. Facebook and BBM (and maybe Twitter) are starting to attack the SMS messaging citadel and it is naive to assume that it will remain impregnable.
  • The voice roaming model will have broken down significantly by 2015. It's already crumbling fast, with regional zero-premium agreements and government intervention. Whilst it's understandable that the operators don't want to hasten its demise, they shouldn't be tying  themselves up in time-consuming knots, in desperate attempts to revive it. That ship hasn't sailed yet, but it's pulling up the gang-plank and if you're honest with yourselves, you'll recognise it.
  • The fallacy that the operators "own the social graph" via the handset phonebook will become even more wrong that it is today. As I discuss in my report on IMS/RCS it's a great example of self-delusion that Mark Zuckerberg must be sniggering about on a daily basis.
  • There will likely be various dual-radio / dual-SIM phones capable of running simultaneous LTE data and GSM voice, without horrible battery impacts. They will also likely be capable of VoIP over HSPA+ where it is reliable. VoIP over LTE will be a nice-to-have, not a must-have, for these users.
  • By 2015, the concept of a link between an operator's access business and its services will have fractured. Many service providers will want VoIP services that can extend outside their own access footprint, without "interoperability" concerns. VoLTE is unsuitable as a basis for operators "own-brand OTT" activities.

Some of the people at operators already know most of this, even though they're trying to ignore the full ramifications. In general, I find that the strategy officers are much more realistic about the challenges than those at the coal-face of the core network - after all, it's not their jobs that are ultimately threatened, so there's less of an incentive to want to BELIEVE in things like IMS as a saviour.

But as well as mine and Gabriel's differences in the vision of voice/telephony - which obviously is subjective and opinion-led - there are some other more hard and concrete issues. He writes " it should be possible to at least match [in VoLTE] the service capability of the existing circuit-switched domain used in 2G and 3G networks."

Capability, yes. But quality? Here, there's an interesting gulf emerging between the "establishment" 3GPP, GSMA and vendors, versus the newcomers such as Skype and Google. The old-school approach to QoS is about packet scheduling, managing latency and delay-sensitive traffic, different classes of service and so on. Get the network to minimise dropped packets, and minimise jitter (variations in latency). The new kids try something different. They assume that there will be problems, and look for work-arounds. Clever buffering techniques, new codecs, packet-loss concealment algorithms, echo-cancellation to deal with weird VoIP side-effects, acoustic wizardry to fool the ear.

IMS and VoLTE is about prevention, while 3rd-party VoIP is about cure.

It's easy to say that "prevention is better than cure", but if it comes years later, is that really true?

Skype acquired Camino, while Google acquired GIPS, specifically to deal with speech processing. The GSMA's IR92 specifications for VoLTE largely ignore this whole area. Speaking to a network vendor yesterday, their view is that the bulk of this responsibility in VoLTE falls to the handset vendors. Yet looking at the Internet companies, my understanding is that their QoE (not QoS) engines involve a complex dance between device and server, watching network quality and adapting in real-time. I don't think VoLTE does that. The application isn't really network- or acoustic-aware. One of IMS's core principles is that applications should be "network agnostic", which is a major point-of-failure for the whole architecture.

Yesterday, I did a conference call over WiFi to personal hotspot, and then via HSPA to the Internet, on to Skype, and finally out to circuit via SkypeOut. It wasn't perfect, but it was perfectly usable. Roll that forward 5 years, and Skype-over-LTE should be better than circuit (HD, built-in ambient noise cancellation and so on). Google Voice over LTE in 2015 will probably feature realtime translation between languages using speech recognition in the cloud. Yes, if the cell is congested there might be some problems with QoS. But I'm willing to bet that the overall QoE will be miles ahead of VoLTE's.

As I've written before, it's pretty clear that 3GPP and GSMA are attempting to use LTE as an excuse to crowbar-in IMS to the operators who've been recalcitrant in adopting it so far. I can use various analogies - it's like Ferrari making a 2-ton boat anchor a mandatory accessory on a new car, or as I put in my most popular-ever blog post, like using LTE as the perch to which to nail the dead parrot of IMS.

In some instances, they may succeed - but perhaps to a bare minimum. For instance, I've recently met an operator who's told me, resignedly, that they might put in a small IMS to handle roaming LTE users. However, he has no intention of offering IMS-based services to his own users.

To be fair to Gabriel, he does sign off the article with a doubt "Can operators reinvent and extend the voice model into billable rich media services? I think it's too early to say". That encapsulates our differences - I also believe that reinventing the voice model is absolutely something that operators need to do. I just think that VoLTE is absolutely the wrong way to approach it. As for "billable rich media services", the answer is maybe - but only if they ditch IMS as a flawed legacy technology and look for other solutions, even if they are proprietary and don't have the false comfort-blanket of interoperablity.

The bottom line is that operators considering investing in VoLTE or IMS need to think twice. What is the actual problem you are attempting to solve, and the business case associated with it? Is it purely a defensive move, and if so is it already too late? Is your "voice" (ie telephony) business as valuable as you think, or is it being inflated by accounting oddities around subsidy repayments and classification of "line access" as voice revenue?

Do you really understand what the difference is between Telephony, and Voice as a whole? Is the old-style telephony service worth replicating in LTE at all - will it be monetisable in 2015 and beyond? Will VoLTE actually deliver good-quality speech when acoustic factors are involved too? Are there ever going to be any IMS mobile services that actually add value and provide a good user experience? Or should LTE be used to introduce a proper vision of "services", "cloud" and "voice", with low-margin legacy phone calls kept for the 2G circuit networks that will be here for another 20 years anyway?

For more detailed analysis and advice on these matters, please contact me at information AT disruptive-analysis DOT com.

22 comments:

Gabriel Brown said...

Quite a bit to discuss. One point of agreement (I think) is that it is hard to determine the value of voice to operators. Because of bundled plans, device subsidies, etc, the value may be overstated in company reports, or may not be. It's hard to know if the customer is buying the device, the minutes, the data, the texts, or what. Probably it's a combination.

One other point. Operators could keep smartphones on HSPA(+) for a few years and put dongles, tablets, and anything that's mainly data-centric, etc, on LTE. I think that's likely.

Will operators want to support carrier-voice in LTE at some point? Yes, I think so. So then, what are the options? And which are they likely to select?

Dean Bubley said...

I agree that some operators will keep phones on HSPA+ for a long while, and put data-type devices on LTE.

But does that mean that VoLTE-enabled handset volumes (and experience curves) are then made even less attractive for the OEMs? What's the per-unit amortised development & opportunity cost for VoLTE- or IMS-enabled phones?

It's a chicken & egg problem 10x worse than something like NFC, because of all the extra horribleness around mobility, electomechanical VoIP acoustics and whatnot.

Some operators will want it nonetheless, yes. Others may just stick with GSM in a Velcro-style device, or rebadge Google Voice built into LTE Android phones.

Or maybe GSMA or OMA or NGMN decides to take a big step NOW and do a proper radio-optimised cloud voice solution.

All the policy vendors are saying they can prioritise particular web apps in the RAN & want Facebook/YouTube/Skype to pay up for their users getting "gold" service. So I've got to believe they could equally well prioritise operatorVoIP.com without much hassle.

Dean

Martin Geddes said...

Ooh! How 2006!

http://ims-insider.blogspot.com/2006/10/ims-is-all-back-to-front.html

http://ims-insider.blogspot.com/2006/08/ims-services-forum-hypothesis.html (scroll to "The Trouble with IMS...")

Gabriel Brown said...

"Or maybe GSMA or OMA or NGMN decides to take a big step NOW and do a proper radio-optimised cloud voice solution."

Not sure what that is. But anyway, is it likely?

"GSM in a Velcro-style device." A dual-radio device probably does make some sense (a la CDMA, & perhaps the TDD folks pick this up), but the 3GPP purists didn't like it. No surprises there.

That's kind of the point I made last night on Twitter. What might be a good idea and what is likely aren't the same thing.

Dean Bubley said...

RAN-optimised cloud voice:

My vision is of an OTT-style voice offering (maybe SIP, maybe not), that has direct hooks to policy engines in the radio & core, which are able to play around with packet-scheduling at the base station to improve latency etc.

Yes, lots of questions "for further study" about security, billing, interop, mobility etc etc. I don't have the whole answer yet.

Essentially it's the answer to the question "Net Neutrality issues aside, what could you do if Skype paid you lots of money to create a higher-quality managed Skype-plus service on your LTE network?" ... and then apply to an operator's own "vanilla" VoIP platform with extra tweaks to differentiate.

If they *couldn't* enable a super-Skype, then all this talk about two-sided business models is nonsense after all.

The balance between a good idea, and what is likely, is not independent of people like you & me commenting on what is possible, and what might be the outcomes if the path of least resistance is followed.

But I agree, one of the *likely* scenarios is a continued & misguided attempt to view VoLTE and IMS as Holy Grails.

Hence, mixing my Python metaphors, I see my role as saying "STOP. No one crosses the Bridge of Death but answers me these questions three, ere the other side he see".

Gabriel Brown said...

"has direct hooks to policy engines in the radio & core, which are able to play around with packet-scheduling at the base station to improve latency etc"

That part sounds like VoLTE. Even VoLGA runs over a packet bearer and would benefit from that.

Two-sided business models is a big subject, not all that well defined, or understood. Suffice to say for now, in the consumer market the opportunity is further out than many a "strategy officer" might like.

Steve Carr said...

as someone who as worked in Carrier Telephony for 30 years I'm always amazed at how much investment has been wasted in failed network architecture frameworks:
ISDN, Intelligent Networks, VoATM, we may as well add IMS to this list.

Dean Bubley said...

On 2SBM - absolutely agree, I have some very serious doubts about the operator's ability to commercialise either API or "network capacity & capability" sold to upstream players, except as glorified-MVNO wholesale products via players like Jasper.

On the other hand, if it starts anywhere, it's with an "eat your own dogfood" proposition. If fixed operators can prioritise & manage their own (non-IMS) IPTV on fixed connections, it should be possible for mobile operators to do the same with non-IMS VoIP.

And as it happens, I'd also agree that a hosted VoLGA-type service could be an ideal mechanism for this.

I'd also expect some of the radio optimisations for VoLTE to be re-used in any other solution which didn't involve a core-network hosted voice app server.

Gabriel Brown said...

@Steve Carr -- fair comment. IMS falls into that category so far.

What would you do to support voice in LTE? Or will that not be necessary for operators?

Anonymous said...

I do not agree completely here.

IMS is doing well. As a matter of fact, I am involved in an IMS deployment which will finally cater to 300 million IMS customers spread across the next 5 years.

The bottom line is, that the operator requires a "standard" architecture that would provide long term stability to support voice, video and messaging services, and also inter-operate with legacy networks (backwards integrate to 2G, 2.5G for voice, messaging and enterprise telephony services).

IMS is the natural answer for this basic requirement. Google voice or Skype-over-LTE are not. They are best effort proprietary services, and not carrier grade.

I am not suggesting that Skype/Google Voice will not do well. But, we need to acknowledge the fact that there are still billions of customers out there who are on legacy 2G networks and they need a way to inter-operate with 3G and 4G subscribers in a "standard" manner.

Franz Edler said...

Hello Dean,
I am missing some important points in your blog.

1.) Emergency calls: as far as I know the Skypes and Googles are not keen enough to take the responsibility for handling emergency calls.
2.) As long as we do not have full LTE coverage (maybe never) voice calls will drop when you get out of reach if you simply rely on VoIP.

I also do not see the move towards IMS as a defense strategy it is the most natural choice if you do not want to invest in a stop gap solution and have some possibilities to evolve.

Franz

Franz Edler said...

Hello Dean,
I am missing some important points in your blog.

1.) Emergency calls: Skype and Google Voice are not keen enough to take the responsibility for handling emergency calls.

2.) As long as we do not have full LTE coverage voice calls will drop when you get out of reach of LTE coverage if you simply rely on VoIP.

I also do not see the move towards IMS as a defense strategy. It is the most natural choice if you do not want to invest in a stop gap solution and you want to have some possibilities to evolve.

Franz

Franz Edler said...

Just a further point to add:

You state that media handling in LTE "isn't really network- or acoustic-aware". That is not true.

Take a look into 3GPP TS 26.114 which applies the RTP/AVPF profile to give immediate feedback on changed network conditions. This enables the sender to reduce immediately the bitrate of the AMR or AMR-WB codec.

Franz

Dean Bubley said...

Thanks Frank, Whitelassi

Franz - changing the bitrate of the codec is only a small part of the story. It doesn't solve a bunch of the inevitable weird VoIP niggles & artifacts that require speech processing.

If you look back at the history of *fixed* VoIP, you'll see that even on a notionally-good connection with good latency & packet loss, there were still acoustic glitches which took years to fix.

I'm expecting the same to occur in mobile VoIP, probably exacerbated by electromechanical effects of device size and mic/speaker placement, doppler shifts during movement and all sorts of other stuff which will appear unexpectedly.

Emergency calls - this is a red herring. I'm not suggesting that operators use Skype or Gtalk "as is" for primary telephony. They have a choice:
- partner those companies to "operator-ise" their services in custom versions
- develop their own optimised, telco-style Skype clones (or acquire & evolve them eg Telefonica/Jajah) which can then be offered to the worldwide Internet user base as well as their access customers
- use 2G or 3G for voice, with LTE for data in dual-radio phone.

As for IMS being a "natural choice", that sounds like a prisoner's Stockholm syndrome to me. And evolve? Yes, it might take you the last steps along an evolutionary dead-end. But LTE offers the unique opportunity to re-engineer the telco DNA for the next 100 years.

Whitelassi - let's challenge some assumptions. *Why* does an operator need a standard architecture in future? Because that's what it's done in the past, rather than develop something unique? Is that why Skype does more R&D than most telcos?

If anything, having LTE as a converged underlying connectivity standard should permit divergence & innovation to occur at the application level. We have standardised electricity supply, but no standards for toaster design.

This "carrier-grade" line about IMS won't wash. It's like a shipbuilder in 1930 complaining that aluminium used in aircraft design isn't iceberg-proof. In-the-network QoS is an increasingly small contributor to overall QoE. Skype's QoE wrapper FAR exceeds most telco services'.

In particular, IMS is exceptionally poor at integrating with the user experience (and evolving with. it) at a handset level. I've been following the evolution of IMS phones for more than 5 years, and we're still not close. Every innovative step forward by Apple or Android or Nokia or Samsung takes us further away still. Add in the web/cloud side and it's even more anachronistic.

Dean

Jim said...

Why do you say that "A significant proportion of voice application usage will be "non-telephony" by 2015" ? To my understanding every voice application is telephony. The fact that the voice application might use your personal computer or smartphone or any other device does not mean that they are "non-telephony". They are ALL telephony.

Dean Bubley said...

Jim, in the sense that the Greek derivation of the word "telephone" means "distant voice", you're technically correct.

But by the same token, that means that shouting across the street, or throwing a CD of Elton John's Greatest Hits like a frisbee is also telephony.

In telecoms parlance, a "telephone call" comes encumbered with a range of technical and regulatory definitions - licencing, numbering, signalling, emergency calls, lawful intercept, record-keeping and so on.

But in essence, telephony refers to Person A calling Person B through a public network for X minutes.

There are many other ways to communicate via voice which don't fall into that category - a taxi dispatcher's two-way radio for example, or player-to-player speech communications in a video game.

The telecom industry itself has had non-telephony services such as push-to-talk.

Historically, telephone calls have been used to access some non-telephony apps & servers, such as retrieving voicemail from a server. But that can equally well be done by VoIP, emailing the sound file and so on.

Telcos are hoping that they can re-use or "distribute" telephony APIs and capabilities for some other applications, such as various communication-enabled business processes. Conferencing is a good example, or cross-team collaboration such as an open voice channel between two offices.

However, I think that many of these other applications do not need the traditional "telephony" service as a building block. There are other ways to construct voice communications without all the extraneous baggage of a phone call. This has already been well-demonstrated on the web and on PCs with voice chat inside IM clients, for example.

Historically, phone calls have (except for private radio) been the default choice for all voice communications.

This is now changing, fast. Against that backdrop, VoLTE is addressing the subset, not the superset, of all voice interaction modes.

Dean

Anonymous said...

Uniqueness and Innovation is appreciated - but not at the cost of interoperability and backwards integration. This is what Skype lacks.

Let us do a small survey where we should ask all major carriers around the world to completely migrate their 2G/3G/4G customers to Skype by 2015. The results of this survey will highlight the need for being "carrier grade".

Just thoughts.

Regards

Aayush

John. said...

The usual tired anti-IMS arguments being trotted out while the rest of the telephony world has already (grudgingly) acknowledged IMS as the future platform for call control (and presumably some other stuff as well - and I don't think anyone considers it a "Holy Grail" much as Dean might like that to be the case).

Let's just assume for a moment that most mobile and fixed operators are going to want to continue to offer a voice service to their customers in 10 years time. What Frankenstein hybrid of Skype/Google are you suggesting that they should adopt? How are they to deal with the slew of regulatory requirements (lawful intercept, emergency service, availability)?

If IMS is not a solution, where are the viable alternatives? The fixed world is already enthusiastically adopting IMS (many of these operators have fixed & mobile operations) - do you not think this success will continue to drive adoption of IMS in mobile networks?

Dean Bubley said...

John - you don't seem to have read the post & comment thread. Aayush, you seem to have misinterpreted things as well.

Nowhere do I suggest that today's Skype or Google Voice are likely to be used for "primary telephony", although it is certainly feasible in various future scenarios.

In 10 years' time, mobile operators will still be using (primarily) 2G or 3G circuit switched if they want to provide primary telephony services. Some may use IMS, if it can be made workable. Some will use Internet-style VoIP of their *own* making or acquisition, quite possibly with add-ons like emergency calling.

Other LTE-only operators will choose NOT to offer primary telephony as a service at all, and invite customers to "bring their own" if they want it.

Bear in mind that in a world of 50 billion mobile connections, there can only be a need for 7 billion primary telephone subscriptions. 80%+ of mobile devices won't need telephony (M2M, tablets, sensors etc).

LTE "happy pipe" data or wholesale-centric players may well choose to completely avoid running in-house voice or telephony services.

IMS and VoLTE *may* be one platform used by *some* mobile operators in *certain* contexts, but it needs to prove itself through performance, useability and business case. So far it hasn't.

It's certainly not a no-brainer, there are plenty of options & we will inevitably end up with a heterogeneous situation.

Ubiquity at the application level is dead. And if IMS *assumes* ubiquity, then it will be dead too.

If VoLTE doesn't interoperate nicely with Skype or Google as peers, it will struggle. They will be the VoIPo3G / VoIPo4G incumbents by the time it launches.

One thing which needs to be included in VoLTE from Day 1 is an easy and effective way to do "freemium" services.

Colin said...

Dean, you hit the nail on its head in many aspects. In the comment sections a few counter-arguments are made in defense of IMS and VoLTE, which I challenge.

But first, I have been involved in VoIP and IMS network architecture, deployment, installation in the last 6 years as a leading architect with one of europe's Tier 1 operators.


1. IMS is doing well. Franz, John and Aayush claim IMS is required for interoperability, emergency calls, Lawfull Intercept, supplemntary services and that operators have accepted IMS as th future of call control. Well, IMS isn't doing well - all major vendors are struggling to sell their platforms, operators do not scale these platforms and the architecture is all 'back-to-front' (credit martin). Major vendors have canned softswitch developments in favor of IMS and that is what they sell. that doesn't mean there are no better architectures thinkable. Second, IMS is so complex, standardization runs far ahead of actual, commercial deployed capabilities it has lost touch, and operators are faced with enormous operational costs to make IMS even work. Third, you don't need IMS for LI, Emergency calls and interoperability. LI can be implemented at routers, SIP proxies and GW. Emergency calls require prioritized traffic handling; operators alreay do this in softswitch VoIP - no need for IMS. Interoperability? VoIP services are connected to PSTN and Mobile telephony using MGCF/MGW. Skype not interoperable with 2G/3G voice - i say SkypeOut. One thing that wasn't mentioned (but probably implied) is feature transparancy. Again, how many of the operators supplementary services work across operator domains. yes they are standadrized, but operators still decide if they want to invest in supporting these features. So today you may have RBT, HD Voice, MMS working as long as th person you call is on the sam network - across netwoks these 'features' tend to break (read the fineprint of your contract almost all operators state they do not guarantee these services to work with other networks). Is that an issue today, apparantly not for end-users.
I m always suprised that people refer to interoperabiity and standardized as a argument for IMS, where it is actually the interface (SIP, RTP, radius/diameter)that provide the interoperability. For standardization, what operators want are standardized interafes (and behaviour on thse interfaces) so that they can select and buy equipment from any vendor they choose.
Stability? Not IMS, it hasn't provided any positive ROIC or ROA.

- Telephony is unique.
Yes, it is. But when wireline oprators started to offer VoIP (at lower price points) or packages suddenly many subscribers 'switched' to VoIP despite quirks in call quality (see comments of Dean) and availability. The success of Skype (both in terms of users and traffic) shows that users do not consider PSTN (and hence Telephony via Mobile) a premium (mobility, however, is considered a premium).

many regards,

Colin

John said...

DT goes straight to IMS (VoLTE), dumping VOLGA: http://www.lightreading.com/document.asp?doc_id=204581

Dean Bubley said...

John

Not surprising, especially given the politics of the situation.

However, I have a reasonable expectation of:

a) VoLTE not living up to expectations (especially in terms of time-to-market) and VoLGA being reincarnated around 2013, perhaps under a face-saving name so that 3GPP/GSMA can grudgingly support it.

and/or

b) Someone doing an OTT version of VoLGA. Perhaps T-Mobile offering VoVL (Voice-over-Verizon's-LTE) using a downloadable client.

Dean