The long anticipated 4G from Verizon wireless is starting to gain spotlight now. As per their plans, Intial testing and deployments will start appearing by the end of the year.
Though we heard that LTE is ready for showtime but despite these statements from telecom leaders, a major challenge is still left un-answered. As we know, 4G or LTE is based on packet switched networks rather than circuit switched that used to be in older standards (3G and 2G). This industry giant leap has added benefits of more bandwidth but has raised a crucial concern about incompatibility with older circuit-switched networks.
Till today we had been living in a circuit switched telecom cores connecting to ip network core as a legacy. IP was never our REAL core as far as Telecom mobile operators are concerned. A drastic movie has brought the issue of integrating the reverse i.e. Mobile core will be IP, and it will connect to older circuit switched networks for services like SMS, voice calls.
Verizon would be the first one but carriers like t-mobile are already ready for it. All of them are facing these challenges and implementing different solutions.
Currently, there are a few ways this problem can be tackled. For SMS and Voice, there is IP Multimedia Subsystem (IMS), the 3GPP way that delivers voice and SMS through IP architecture, like a VoIP system with messaging enabled. There is network hybridization, where the 4G network would only handle data and the legacy 2G/3G networks would handle voice and SMS. Finally, there is a Forum called VoLGA, or Voice over LTE via Generic Access, a spec based upon 3GPP’s GAN standard(wikipedia), which allows circuit switched traffic to be encapsulated into LTE packets.
VoLGA is backed by a Forum of wireless industry leaders such as Alcatel-Lucent, ZTE, Starent Networks, Nortel, and Ericsson, as well as consumer electronics companies LG, Motorola, Samsung, and Huawei, which are collectively known as the VoLGA Forum.
At the LTE Forum in May, T-Mobile’s core network architecture lead Franz Seiser said, “There’s a big risk if we don’t decide how to go forward with our cash cow…If we don’t get this right, we could put the whole of LTE at risk.”
The point is if more carriers are unified behind VoLGA, it is more likely to be approved as a 3GPP standard, and the technology could then move forward crossing the hurdles created today. Even though it is already a 3GPP standard, IMS innovation is reportedly slow and costly, and voLGA is a better alternative.
voLGA forum recently made a milestone with its second draft of the VoLGA spec in May, and estimates on wrapping-up by the end of the year to submit it to 3GPP release 10, the LTE Advanced official standard.
We hope to see more Carriers joining the Forum and making life of 4G demanding consumer easier.