That calls for new options on radio networks but also new ways of sharing those networks, Tolaga's Marshall said. Subscribers use mobile broadband services in a pretty consistent way, while many IoT devices like sensors send bursts of traffic that aren't always urgent. It takes a lot of overhead to make all those uses share a network, so 5G may include a special way to handle bursty traffic that's more like the way Wi-Fi works, he said.
It's also becoming more obvious that 5G will have to connect things like self-driving cars and augmented-reality headsets. Those need data to arrive right on time. For one thing, 4G can't get below 10 milliseconds of latency, so that will have to change. Marshall said. But the next standard may also mean a whole new network architecture with less information in centralized data centers and more spread around its edges, including in devices, he said.
For example, if a cluster of cars going down a highway needs information about each other to keep from colliding, a conventional network can't handle it if there are more than two cars, he said. At that point, delays in getting to a central cloud are too long, so the data has to stay local. "The cloud ... has to be embedded in the car," Marshall said.
Needs and possible solutions got clearer this year, but 5G development is far from done. Next, those crafting the standard will have to decide what goes into the first release of 5G and what will have to wait for later updates. They won't finish hashing that out in 2016, Marshall said.
Still, everyone wants to be out in front of 5G development and deployment, and 2015 saw a lot of jockeying for position.
Just like 3G and 4G, the 5G specification will be drawn up by the 3GPP (Third-Generation Partnership Project) and approved by the International Telecommunication Union. But vendors and policymakers want to influence the standard. In October, several large regional groups agreed to hold meetings every six months to build consensus on what should go into 5G. That followed a similar agreement-to-agree in September between China and the European Union.
Even with the standard still about five years away, 2015 was a good year for promises of the first 5G network. NTT DoCoMo said it would roll out the first commercial system ahead of the 2020 Summer Olympics in Tokyo. South Korea's KT Telecom said it would have one in 2018 for that country's Winter Olympics. Verizon Wireless went one better, claiming it would start field trials of 5G in 2016, leaving some observers to ask exactly what kind of 5G that might be.
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