Public safety broadband network could be used for voice

A technical requirement and suggestions document for the future national public safety broadband network leaves the door open to the network's use for voice as well as data connectivity and also gives a small sense of the concept of operations the network will operate under.

A board established by the Federal Communications Commission consisting of private- and public- sector representatives transmitted June 21 the technical document (.pdf) to the First Responder Network Authority, aka FirstNet, the independent authority within the National Telecommunications and Information Administration created earlier this year to set up the public safety broadband network.

Among the recommendations of the board is that the public safety network support Voice over LTE capabilities--the FCC already selected LTE in 2011 as the common air interface for the network.

VoLTE, the board notes, has yet to be deployed commercially within the United States and so isn't a network requirement, since "it is not prudent to require FirstNet to advance ahead of commercial service provider deployments."

They also note that its use within the public safety broadband network will at first be less functional than its eventual application in commercial networks because while commercial providers will have recourse to switching a VoLTE call to other radio technologies if a user leaves the area of LTE coverage, if a public safety user goes outside the area of public safety broadband network coverage, "the call will drop."

Consequently, deployment of VoLTE may need to wait until there is significant regional national public safety broadband network coverage.

The board could have recommended voice over Internet protocol, but since VoIP is a best effort application, "it doesn't come with the reliability, it doesn't come with the quality" that current public safety voice service has, said Peter Jarich, research director of wireless infrastructure and converged core at Current Analysis, a market intelligence firm based in Washington, D.C.

VoIP standards are also proprietary, he added, meaning that FirstNet would be in the position of selecting one vendor over another.

As for concept of operations, the technical document says the network must support prioritization and quality of service of communications, permitting "high priority users can establish connections with a higher level of certainty relative to low priority users." Criteria for determining high-priority users includes role, application types and incident type, the board says.

The network must also include usage-based billing, the board says, "because of the way most consolidated/regional systems are funded"

Most state information technology agencies don't receive direct appropriated funding and so must charge users for services rendered. "Therefore it is extremely important that these types of organizations can identify the appropriate entity/person to re-bill," the board says.

For more:
- download the board's recommendations (.pdf)

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