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Dispelling LTE Myths - The 3GPP Empire strikes back

 
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Dispelling LTE Myths - The 3GPP Empire strikes back
by Moray Rumney - Tuesday, 17 November 2009, 3:58 PM
 
On the home page of 3GPP is a link to http://www.3gpp.org/Dispelling-LTE-Myths which addresses concerns with aspects of LTE deployment covering:
  • Support for voice
  • Supoort for SMS
  • Readiness of IMS
  • Support for emergency calling
How do Forum members perceive this development? Is this a convincing rebuttal of the issues?

Moray.
Picture of Dean Bubley
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Dean Bubley - Tuesday, 17 November 2009, 5:44 PM
 
Nothing new really.

It takes a very narrow view that "maturity" equals "fully specified". It still maintains that "The voice solution for LTE is IMS VoIP and it is fully specified" and that any other solution is merely a "transition".

In other words, it makes LTE sound unsuitable for those operators which are IP-centric but which do not believe in IMS as a suitable control/service solution.

3GPP is trying to use LTE as a lever to force unwilling operators to adopt IMS. This will fail.

SMS-over-SGs has some serious shortcoming as well as costs, but is probably OK as a short term solution.

I am moving to the view that current LTE is the equivalent of Windows Vista, while HSPA = XP

I think a lot of operators will wait until "Windows 7" becomes available, either LTE Advanced or perhaps Rel 10 LTE.

Dean
Picture of Gabriel Brown
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Gabriel Brown - Wednesday, 18 November 2009, 9:27 AM
 
Aspects of Rel 10 are pretty much a given for most operators.

Picture of Moray Rumney
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Moray Rumney - Wednesday, 18 November 2009, 10:22 AM
 
So if LTE-Advanced, Rel-10, aka Windows 7 is the answer can we get a bit more specific?

What exactly in LTE-Advanced, Rel-10 is essential to making LTE viable? My view of LTE-Advanced is coming from the perspective of carrier aggregation, 1 Gbps, 8x8 MIMO and Relaying - all of which are doubtful but I ssupect it is the network aspects that are beign alluded to here.

Moray.
Picture of Gabriel Brown
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Gabriel Brown - Wednesday, 18 November 2009, 11:40 AM
 
Sorry, I meant R9.

Like you say, carrier aggregation, 1 Gbps, 8x8 MIMO and Relaying are part of LTE Adavnced. But won't R10 cover "left overs" from R9?

E.g VoLGA could be in R10 (assuming it gets anywhere).

Picture of Moray Rumney
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Moray Rumney - Wednesday, 18 November 2009, 3:19 PM
 
There is always an element of spill-over from one release to the next. For a comprehensive list of what is actually in any one release see http://www.3gpp.org/ftp/Information/WORK_PLAN/Description_Releases/

Moray.
Picture of Gabriel Brown
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Gabriel Brown - Monday, 23 November 2009, 2:58 PM
 
Yes, but like Dean says, it's one thing having a feature specced into 3GPP, quite another to have it useable. Changes and additions in subsequent releases are often needed.
Picture of Gabriel Brown
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Gabriel Brown - Wednesday, 18 November 2009, 9:34 AM
 
It seems more like a reaction to shrill vendors/media/bloggers/analysts (I'm an analyst, so hold my hand up here).

Fwiw, 3G provides a lot of lessons for LTE -- mostly that it takes time to succesfully deploy a new generation of mobile technology.

Four years ago lots of people were bellyaching about 3G and how it would never work, how the devices were junk, how inter RAT handover was so bad, etc. It's now working just fine. In fact, HSPA is a phenomenal technology.
Picture of Dean Bubley
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Dean Bubley - Monday, 23 November 2009, 9:17 AM
 
Gabriel - I agree, but that's part of the problem. HSPA is indeed very good & has scope for further evolution, and so I see very little argument about transitioning to LTE early. To use another software analogy.... wait for the first service pack with the most important bug fixes.

Moray - I wouldn't necessarily pick out individual technical features, but just the overall process of "optimising the ecosystem". In the case of 3G it was about device battery life, convenience & business model (culminating in HSDPA dongles & smartphones).

It's unclear what extra LTE can bring to the table - in fact, there's likely to be lots of retrograde steps around power, device availability, lack of workable voice solution, more handover issues, more IPR complexity etc etc.




Picture of Zigurd Mednieks
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Zigurd Mednieks - Monday, 23 November 2009, 2:51 PM
 
If you are a CDMA carrier and CDMA data lacks the HSPA road map, LTE makes a lot more sense, especially if your main global partneris also going to roll out LTE.
Picture of Dean Bubley
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Dean Bubley - Monday, 23 November 2009, 5:05 PM
 
Zigurd: " If you are a CDMA carrier and CDMA data lacks the HSPA road map, LTE makes a lot more sense, especially if your main global partneris also going to roll out LTE."

And what if you're a CDMA carrier with:

- a unique frequency band for LTE optimised for coverage rather than capacity, and which could make MIMO antennas rather difficult in compact devices
- your main global partner is in no obvious hurry for LTE deployment
- your Chinese partner wants to do LTE in a different band with TDD rather than FDD
- your main domestic rival could play Game Theory and delay its own LTE rollout to reduce early scale economies for devices, pushing up your costs.

Not to mention that you can't even gain marketing advantage using inaccurate terms like "4G" as another rival is already using that (equally wrongly) for another 3G technology.
Picture of Sadin Nurkic
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Sadin Nurkic - Tuesday, 24 November 2009, 11:39 AM
 
Hi all,

Sorry to butt-in on the discussion, but this one has really got me puzzled. 3GPP must be responding to the hype, without even considering their own reasons for moving to LTE.

HSPA doesn't carry voice either, it falls back to R99 to do a voice call. So I'm failing to understand why does it matter that LTE doesn't have a voice solution? This surely cannot be the only differentiator to go or not to go to LTE. In this world of dual/tripple/quad/etc. band handsets supporting multiple technologies - 2G,3G-R99,3G-HSPA, etc. does not supporting voice on one of them really matter?

One thing that keeps getting forgotten about in this discussion of LTE voice, is that LTE is *NOT* meant for voice - it is a wireless DATA network. The fact that you can also carry voice over data means that someday, through some variant of VoIP (or IMS) you could have voice on LTE. In fact you can run Voice on top of 3G-R99 data or HSPA data today, so running it on top of LTE won't be an issue. It is more of an issue of how interconnect is done, how multiple accesses networks are managed from QoS and signaling points of view and the relevant local/mobile numbers are handled. Skype solves this issue mostly, so I'm sure the operators will - one day... :)

So my take on things is:
LTE will deploy in commercial environments that have pressing needs to give higher throughput to end DATA customers or to those operators that want greater efficiency across their radio network. However this does not mean they can turn off 3G/HSPA networks - and probably won't for a while. However through advancements, it is possible to either support 3G/HSPA on the same equipment as LTE or there would be a possibility to simulate it - femto-like? lowering the total cost of ownership for operators. On the topic of inter-technology handovers - stats on mobile broadband (primary customer for LTE?) are that upwards of 80% of users are static = no handover.

Also today there are no 3G only operators in the world - well there are, but they ALL roam on 2G networks in some way. So if the operators are unable to turn off 2G networks after all these years, are they really going to be turning off 3G/HSPA networks soon (where soon=10 years)? The question is more around which equipment vendor will come up with 2G/3G/HSPA/LTE eNodeBs and the relevant support structure to replace existing equipment.

So this is far from WinXP vs Vista debate where the two are mutually exclusive - LTE and 3G/HSPA and even 2G are not mutually exclusive and in some case they're all mandatory (handset and network side of things). This all doesn't deny that HSPA+/evolution is suitable for most end-customers; just that you don't need (traditional) voice for LTE.

Sadin.
Picture of Sebastian Thalanany
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Sebastian Thalanany - Tuesday, 24 November 2009, 12:47 PM
 
Thanks, Sadin.

Agree with your perspective.

A multi-faceted world indeed.

Regards,
Sebastian
Picture of Moray Rumney
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Moray Rumney - Tuesday, 24 November 2009, 1:58 PM
 
Sadin,

Don't apologize for butting in - the more butts the better! You ask a lot of good questions that demand good answers.

You are right about HSPA and voice, the service is carried over circuit-switched dedicated channels for which CDMA is an excellent solution in terms of QoS and capacity. However, this is not a fall back scenario from HSPA, it is very much the designed parallel operation that caries none of the drawbacks associated with CSFB from LTE to 2G or 3G.

You ask why a voice solution matters to LTE when it is primarily a data service. The reason needs to be looked at from the other direction. For an LTE-enabled smart phone on an LTE connection, an incoming voice page will cause the LTE link to ungraciously drop to enable the voice call to be picked up on 2G or 3G after some delay. The state of the LTE connection and any apps is presumably left indeterminate. For a data-only dongle the problem is much less.

So LTE may not be targetting voice, but withouth voice support, the voice service will destroy the LTE link. That is a new problem for which the industry has yet to agree one solution. I think there are around 6 on the table and no silver bullets. The prospect is further fragmentation.

Dual transceivers could help but considerably drive up costs.

Your points about the longevity of 2G and 3G are well taken and I agree it will be a long time before legacy networks are turned off, particualrly when there is still active evelopment on EDGE and HSPA.

What remains to be proven is whether deployment constraints - primarily due to spectrum limitations - will enable LTE to emerge as a significantly higher efficiency or higher capacity air interface. This is a complex subject which has no single answer as it depends on the operator's particular footprint. One critical element of this is that LTE's efficiency in the same bandwidth is similar to HSPA+ (within 20% on paper) so the big difference comes with spectrum.

If an operator does not have new spectrum, switching to LTE would not look good. If new spectrum is available, the choice of technology is still not clear since the economies of scale of extending an HSPA network, e.g. AT&T's stated plans, has to be compared to the cost of operating a new network and dealing with the fragmentation and interworking issues. The dynamics for a new operator with no legacy network are different again but worldwide scale matters here if device costs are to be kept low, and multi-format multi-band 2G + 3G + 4G devices will be anything but cheap for a very long time.

Moray.
Picture of Kent Wallenrud
Re: Dispelling LTE Myths - The 3GPP Empire strikes back
by Kent Wallenrud - Thursday, 10 December 2009, 8:40 AM
 
I have not posted anything here for a long time. I just felt that I had to get a few feelings out (most of which I can't express in english).

I have analysed the wireless industry the last five years with an inevitable emphasis on the future of LTE. I think I could fairly say that I have done this in the broadest possible sense collecting a large number of pieces of information in the big puzzle. I have more pieces than I can keep in my head at the same time.

I regularly write updates on my view to ZTE. This is what I am doing right now This works also for me as an update to my own brain by having to take out all the pices and view the big picture.

And this is when the big question pops up:

WHY BOTHER ABOUT LTE AT ALL??

I will go home today and flip my guitar over and start to play Tarrega left-handed!

Kent