Standards for mission-critical push-to-talk functionality on an LTE network are scheduled to be completed in less than two years, but other factors likely will play a role in determining when LTE is accepted by first responders in the marketplace, according to speakers at last week’s Public Safety Communications Research (PSCR) stakeholders conference.

Delivering public-safety functionality has become a high priority within 3GPP—the standards body that oversees LTE development—thanks to the establishment of FirstNet in the U.S., the United Kingdom’s declaration that it wants to replace its TETRA system with LTE in 2016, and other global interest, according to Andrew Thiessen, division chief for the Institute of Telecommunications Sciences (ITS).

As a result, characteristics that are important to first responders—for example, direct-mode communications and group communications—are expected to be introduced in Release 12 of LTE and completed in Release 13, Thiessen said. A mission-critical push-to-talk capability is slated to be part of Release 13.

Release 12 is scheduled for completion in December this year, and Release 13 is expected to be finalized in March 2016. News of this timeline could be troublesome for public-safety entities with LMR systems that are approaching end of life, because it is not clear what the next step should be to offer mission-critical voice communications, according to attendee Bill Schrier, who is the state point of contact for the state of Washington.

“If I was an elected official—or the legislative assistant to an elected official, or an auditor—who is facing a major investment in LMR and I looked at these slides and saw that the United Kingdom wants to implement [mission-critical voice over LTE] in 2016, I’d say, ‘Gee, why should we make investments in LMR? Why should we make any more than the minimum investment in LMR? We’ll just wait until the standards are ready, and then FirstNet will be able to do mission-critical within five years,’” Schrier said.

“My question is: There have to some flies in the ointment here—some potential ‘gotchas’—on this timeline that we can anticipate now. I can tell you one right away, which is: ‘Do you want to trust the safety of your responders to Release 1 of anything, like the first release of mission-critical voice over LTE?’"

Thiessen acknowledged that the consensus-centric methodology used to establish 3GPP standards makes it vulnerable to potential delays—“it only takes two or three organizations to object to [standards] work to bring it to a screeching halt,” he said—but that has not been an issue recently for the key public-safety functionalities.