MythBusters: A FirstNet edition

“5G will be commercially available by 2020. FirstNet’s system is based on LTE, so it will be technologically obsolete by the time it is finished as scheduled in 2022”: This could be viewed a logical statement, based on past generational transitions associated with cellular technology that required a carrier to “rip and replace” existing infrastructure equipment to migrate from 2G to 3G, for example.

However, the transition between 4G LTE and 5G promises to be different, because of the nature of LTE, which stands for “Long Term Evolution.” The evolutionary aspect of LTE is designed to let network operators leverage their infrastructure equipment for as long as possible, with many of significant performance and functionality gains being managed through software.

LTE standards are created through the 3GPP standards body, which is slated to complete Release 14 of the LTE standard this year. The Release 15 standard is supposed to be the first 5G release and is scheduled to be completed in 2018. In other words, the infrastructure needed to support 5G is designed to enable a smooth transition from 4G LTE, particularly as we see the densification of RF nodes—such as small cells—deployed in LTE networks.

“FirstNet’s system will not provide coverage in rural areas”: In the early days of FirstNet, this was a big fear among public-safety representatives, based on FirstNet’s apparent financial dilemma: FirstNet was tasked to build an NSPBN that likely would cost $30 billion to $50 billion, but Congress only earmarked $7 billion for the project.

As a result, there were many concerns that FirstNet would be built only in major metropolitan areas—locations where potential commercial partners needed additional spectrum and could make money—and there would not be enough funding left to provide rural coverage.

But this fear was unfounded. Congress mandated that FirstNet provide rural coverage, and the FirstNet RFP includes rural network-deployment milestones in every construction phase. There is no question that FirstNet will provide rural coverage, although some state officials have grumbled about the definition of “rural” that is used by FirstNet.

“AT&T cannot provide the 2G coverage in rural areas that is depicted on coverage maps, because the AT&T retired its 2G network”: This is a new statement based on last week’s release of the coverage map found on www.firstnet.com. It is true that AT&T no longer operates a 2G wireless network, but some of its carrier partners that will provide FirstNet coverage in rural areas still provide 2G service.

All 2G areas reflected on the coverage map represent areas where AT&T will depend on a carrier partner to provide terrestrial wireless coverage, an AT&T spokesman confirmed last week.

“AT&T’s FirstNet offering is no different than the service that is available today from commercial carriers”: It is true that FirstNet subscribers will use AT&T’s commercial wireless infrastructure until the NPSBN is deployed on FirstNet’s 700 MHz Band 14 spectrum within a particular geographic area. It is also true that first-responder agencies today can get prioritized access on the commercial networks of AT&T and Verizon, but the similarities end there.

Today, both AT&T and Verizon charge monthly premiums for priority access on their commercial networks. As part of FirstNet, AT&T will not charge public-safety users for priority access across its commercial network. More important, AT&T has pledged that FirstNet public-safety subscribers will get preemptive access or “ruthless preemption” to all of AT&T’s commercial networks—a capability that will extend to the Band 14 NPSBN when it is deployed in an area.

No carrier today offers preemptive access to their commercial networks. In fact, public-safety officials advocating for first responders to get the D Block spectrum repeatedly have said that the turning point in the debate on Capitol Hill occurred when representatives for Verizon and AT&T said the carriers would never give public-safety users preemptive access to their commercial networks, because it would not be in their shareholders’ best interests.

What’s the difference between priority and preemption? Here’s a simplified explanation:

With priority access, a public-safety user would go to the “front of the line (or queue)” to get the next available bandwidth resources provided by the relevant cell sector serving the user’s geographic location. However, if the cell sector already is saturated completely by users, there is a theoretical possibility that the prioritized public-safety user might not get the requested services (note: this is much less likely on an LTE broadband network than is it in a LMR system—particularly with as many spectrum-band options as AT&T—but it is theoretically possible for service to be denied to a priority user).

With preemptive access, a public-safety user not only would move to the front of the queue, but the user automatically would get on the network and be given the bandwidth requested.