Verizon Wireless and LTE - don't be so hasty

Interesting to see yesterday's Verizon's announcement about its LTE trial & deployment intentions with Vodafone. It's been an open area of discussion that the company has been interested in LTE for some months now, although I've been a little warier than some in describing this as a death-knell for CDMA UMB.

While I agree that the statement is pretty definitive, there's still a number of unanswered questions & scenarios that could play out:

• Firstly - it's a trial. Until the trial is proven successful, presumably the chequebook stays in Verizon's pocket.
• Secondly, as Sprint's current review of its deployment of WiMAX illustrates, it's always possible to change direction at a later stage if necessary.
  
• Verizon is likely to keep (and evolve) its existing 3G EVDO Rev A network irrespective of LTE. Its news release says that it will "continue the expansion" of its existing technologies. Although Rev B isn't getting much traction either, I guess there's scope for a Rev A+ of some sort.
  
• The big 'swing' factor for UMB continues to be Japanese operator KDDI. If it also backs away from the CDMA family, then its pretty much goodnight for UMB. If it runs with it, then there's possible large scale deployments to follow in places like India or Brazil.
  
• Another variable is of course SprintNextel, the other big US CDMA operator. Don't forget that it originally trialled Flarion's Flash-OFDM (on which UMB is based, since Qualcomm's acquisition of Flarion), and quite liked it - but felt it wasn't ready for deployment back in 2006. If Sprint backs away from WiMAX (or scales its rollout down), I can't see it necessarily wanting another 3.5G+ technology in the shape of LTE.
• Lastly - it's unclear what might happen if Vodafone & VZW ever parted company.
  

My gut feel is still that I see full radio convergence more in the timeframe of the next step beyond LTE, lets call it ELTE (Even Longer Term Evolution). But I could certainly buy the notion that Verizon might want a converged access network that looks like SAE in the meantime, which could connect together multiple radio standards.

Essentially, I see convergence between 3GPP and 3GPP2 extending from the core outwards for major carriers:

Stage 1 - Core Network (IMS or something similar), Now
Stage 2 - Radio Access & Transport (aggregating LTE together with HSPA, EVDO, WiFi, TD-SCDMA and maybe WiMAX), around 2011
Stage 3 - Air Interface becomes fully harmonised (excluding things like TD-SCDMA probably), around 2015

That said, the option to create dual-mode CDMA/LTE devices could help Verizon manage multiple networks. And if it did, then it would definitely also create an interesting backdrop for how it treats voice - would it use VoIP on LTE, and circuit on EVDO? Or VoIP everywhere?