With 5G deployments just a few years away, the question of how mobile operators will have enough bandwidth to support future rollouts is one being discussed at the highest levels of every telco internationally.
Consider this: there were an estimated 6.4 billion connected “Things” at the end of 2016, according to research outfit Gartner. That will top 20.8 billion by 2020, according to the same analyst firm. A number of vendors, from Ericsson to Cisco, predict it could be more than double that.
All of those devices will require connectivity, and much of it will be mobile, but spectrum is a finite and expensive resource. That is why operators are looking at ways of freeing up their existing spectrum holdings.
AT&T has already switched off its 2G network to free up spectrum, with Verizon and T-Mobile set to follow suit. At this year’s Mobile World Congress, T-Mobile US’s CTO, Neville Ray, talked about not only switching off 2G, but also turning off its 3G network as well.
“When we move to 5G, I don’t want to have a 2G or 3G network behind me,” Ray said. “LTE is not dead yet. It is where we build the foundations.”
Legacy presents challenges. Ray admitted there were problems to this, however, most notably around legacy voice technology and handsets. In order for T-Mobile to switch off its legacy infrastructure, it would need all customers to have access to either voice over LTE (VoLTE) or voice over IP (VoIP) services. This means handset upgrades for a number of customers.
Ray says: “There is a big problem around legacy handsets. We all understand US handset refresh cycles, right? We’ve already got two million customers using VoLTE – we think that is one of the highest numbers around – but we need more to go all LTE.”
What to do with voice data isn’t the only challenge with switching off 2G and 3G. There are also major problems around legacy machine-to-machine services that rely on a 2G SIM. Even though new IoT standards around low powered, wide area networks could ultimately replace 2G M2M connections, there is still the issue of actually physically upgrading them.
Telefónica CTO Enrique Blanco exclusively told GTB that he does have plans to turn off 2G, but it is unlikely to do so in the next five years.
The reason for this, he explained, was because there were some small issues that have to be resolved first – most notably, reducing the complexity of the Spanish giant’s 2G network.
“Switching off the 2G is a must,” Blanco said. “But there is a small issue to solve. First of all, the machine to machine users. We could switch it off tomorrow but we have customers who we would need to migrate.
“We have to guarantee that in the next two years we reduce the complexity of 2G and minimise our spectrum use. To do our refarming, we need to minimise the number of customers using it. We can switch it off in the next five years.” He did offer a solution, however, that would see national roaming agreements set up for 2G. That way, rival operators could maintain just a small amount of 2G bandwidth to support a small network and use other networks when necessary. On 3G, Blanco said it would take longer, perhaps up to a decade.
This is because even if Telefónica manages to push all customers on to VoLTE services, it will still need to support 3G.
This shows the diversity across different markets, and across strategy at the major telcos. For now, however, it appears a full 2G switch off globally is some way away. And as for 3G? Ray’s ambitions are perhaps a little too ambitious for the moment.