LAS VEGAS — AT&T’s Jan. 3 announcement that it will launch mobile 5G service in 12 markets by year-end had some skeptics questioning the feasibility of that plan. Although the 3GPP released the non-standalone 5G NR standard in late December, the entire 3GPP Release 15 5G standard won’t be completed until June, making for an extremely fast turnaround.

Nevertheless, Gordon Mansfield, VP of RAN and device design at AT&T, told SDxCentral in an interview at CES 2018 last week that while AT&T’s plan is aggressive, it is possible because of all the work AT&T has been doing to its network over the past three years.

Specifically, Mansfield said that the company’s migration to a cloud-RAN architecture will help AT&T because it means the company only has to install a new 5G NR radio on the tower and use software to handle most of the other network upgrades, depending upon the vendor selected by AT&T. However, Mansfield noted that because it’s so early in the 5G standards process, AT&T will likely add extra protection to its network and install a separate baseband instead of just deploying a software layer.

Interestingly, Mansfield also said that the rollout of 5G will be easier than past upgrades, for example from 3G to 4G LTE, because the underlying control plane that will manage the 5G network will still be the existing LTE control plane. That means in areas where there is a 5G radio deployed, the network will notify the user’s 5G device and that will turn on the 5G radio in the device so the user can receive the 5G signal. When the user in not in a 5G market, the device will just operate on the existing LTE network. “Anywhere there is a 5G radio, the 5G network will kick in,” Mansfield said. “This is much easier than previous technologies because the control plane is LTE.”

Mansfield added that because the control plane is LTE there will be no hard handoff. In other words, the device will remain connected, and the network will not have to “hand off” the signal from the 4G network to the 5G network. Handoffs have historically been a problem for wireless operators and the reason for dropped calls and lost data connections.

But even though the 3GPP has released its non-standalone 5G NR standard AT&T still has to wait for the full 3GPP Release 15 standard in June so it can build a fully compliant 5G network.

Perhaps because it is waiting for the Release 15, AT&T has not revealed any of the vendors for its 5G network or 5G devices. Mansfield said that although the company has not made any partner announcements it has a pretty good idea of the companies it will be using for each part of the network.

When asked if any of these vendors might be smaller or non-traditional telecom vendors, Mansfield remained cagey but added: “Nothing is off the table.”

Also unclear is exactly how AT&T will rollout those 12 5G markets. Will it light up all 12 markets at once or do some sort of rolling launch?  Mansfield said those plans are not complete.