How LTE is enabling mission-critical networks

The maturity of LTE is increasingly enabling commercial mobile network operators to offer mission-critical, rather than best-effort, infrastructure and services, according to Patrik Ringqvist, principal solutions architect for Ericsson North America. Ringqvist, who focuses on critical communications, said that he considers “mission-critical” to be “the ability to communicate when you need to, where you need to” — which, he added, is a description that is more complicated than it might seem. Coverage is the first requirement, and he said that different types of mission-critical communications can have different coverage requirements — which is part of why the public safety community pushed for access to specific spectrum and it own network, which ultimately took the form of AT&T being awarded the contract for the First Responders Network Authority network. The reliability and availability of the network are also what differentiate mission-critical networks, he added. “You need to build to a different standard than, maybe, most operators are used to doing, and of course, both the coverage and availability maybe takes a little bit more investment,” he said, adding that the additional expense has historically been a barrier to true mission-critical network infrastructure. However, the maturity of LTE as a technology and ecosystem is changing that, he added, with low-band spectrum (such as FirstNet’s 700 MHz) enabling better coverage options both indoors and outside and in rural areas, and LTE-specific reliability features such as enabling specific quality of service rules for particular users and being able to prioritize their access to the network. “Those have enabled us to build mission-critical networks with LTE that we perhaps were not able to do in previous generations of wireless technologies,” said Ringqvist. The LTE release roadmap specifically provides for mission-critical features including mission-critical push-to-talk as well as mission-critical video and data. Although MCPTT was first introduced in LTE standards in 2016, it is only recently that operators have started to look at implementing it. Verizon has said that it plans to start rolling out the feature in its network later this year — as an augmentation to Land Mobile Radio for first responders rather than as a replacement, to start. AT&T-FirstNet, meanwhile, has already put out a request for proposals to vendors to provide MCPTT, according to Chris Sambar, SVP for AT&T-FirstNet. Sambar, who said that MCPTT is one of the first capabilities that first responders ask about, expects to have solutions in the lab later this year, with the technology to go live in the network early next year.