Telecoms Announce "One Voice" Initiative To Promote LTE Wireless Broadband Stand
suraj.sun writes to mention that Long Term Evolution (LTE) networks may have just gotten a boost over WiMax in the battle for wireless broadband dominance. A group of telecom companies has created the "One Voice" initiative, designed to promote a standard that will provide interoperability for broadband voice and SMS. "LTE has been fine at supporting data, which uses IP-based packet switching. But it's faced challenges trying to incorporate traditional circuit-based switching voice and SMS services onto IP-based networks. One Voice is the group's attempt to resolve that issue. The new specification will use existing functionality known as IP Multimedia Subsystem (IMS), which already defines how to provide data, voice, and other content over an IP-based network. IMS was established by the 3rd Generation Partnership Project (3GPP), a group comprised of telecom industry associations trying to set standards for 3G mobile networks."
LTE and WiMAX are the main competing 4G technologies. Both LTE and WiMAX are all-IP networks. No circuits. No dedicated channels for voice. If you run voice on 4G it will be packet voice no matter the other technology choices.
One Voice is what this consortium is calling IMS for 4G. IMS uses SIP for signaling. That makes IMS more like the kind of packet voice you find in Asterisk. Except IMS includes a lot of additional standards that, among other things, enables it to replace the signaling used in circuit switched networks and still interface to those networks. Some people favor IMS because it is the officially accepted 3GPP standard for these types of networks. Other people don't like IMS because it is too complicated and includes a lot of stuff that is unlikely to be used, including stuff like using SIP to initiate Web sessions so you can charge for them. Not that anyone would accept that kind of product.
The other consortium that pushing a voice call standard for LTE is called VoLGaA Forum. VoLGA stands for "Voice over LTE General Access." It works like UMA, which is a way of extending the circuit switched mobile signaling over IP. So you can buy these UMA "femtocells" - a really small cell site - and put them in your home or office and hook them up to your Internet service to extend mobile access to those locations. VoLGA is UMA scaled up to the whole network. Pretty suave, especially for the networks that already support UMA - you can re-use a lot of the same systems.
WiMAX never flirted with UMA (as far as I know) and I think most WiMAX networks that support voice will use IMS. Which is what One Voice is promoting for LTE. So that's no disadvantage for WiMAX.
You may be thinking "If it's all packet voice, why don't I put a SIP client on my smartphone and use my company's IP PBX? Or, why don't I use a smartphone Skype app?" That's called an over-the-top service (OTT). Which is why SMS is so... "important" to this discussion: The only thing you lose by using an OTT service, is SMS.
I wrote parts of this stuff