PhilMarshall-113NEW ANALYSIS: Mobile communication networks are now an underlying fabric of most societies, but are prone to overload and failure during major crises, such as natural disasters.

For this reason, dedicated public safety networks have been deployed, and a variety of trunked radio technologies used, including legacy analogue (for example MPT-1327), digital mobile radio, P25, Tetrapol and TETRA. In many cases, individual public safety agencies have deployed their own private networks. These networks function adequately within the operational silos of the individual agencies, but become problematic during major events, when inter-agency communications are needed.

Furthermore, since digital trunked radio technologies only support voice telephony and narrowband data services, they cannot provide the broadband connectivity needed for situational awareness capabilities (for example, smart city video surveillance). Public safety agents commonly rely on commercial mobile networks for these broadband capabilities.

The 3GPP, which is responsible for 4G-LTE standardisation, is developing features specifically targeted towards business and mission critical services, such as those required for public safety. These features include prioritised and preemptive network access to ensure mission critical services continue to function during emergencies. They also include specific service capabilities such as push-to-talk (P2T) and group communications.

Global standard
Because of these capabilities, and others which will be developed in 3GPP Release 14 and 15, it is generally recognised that LTE will be the standard used for public safety in the future. Public safety LTE (PS-LTE) network equipment is provided by a variety of vendors, including Huawei, Nokia, and Motorola. PS-LTE is already being used (or planned) in several countries including Australia, South Korea, Qatar, UAE, the US, and the UK.

Although LTE is earmarked for public safety, there are several challenges countries must overcome for its adoption. Specifically, PS-LTE requires adequate funding for spectrum and network resources, and to support ongoing service delivery. Although most countries have dedicated trunked radio spectrum, the allocations are narrowband and, unless harmonised, not suitable for PS-LTE.

In some countries, such as France, South Korea, the US and Canada, dedicated broadband spectrum has been allocated specifically for public protection and disaster relief services. Most regulators have yet to allocate dedicated spectrum, or have no plans to do so. In countries without dedicated spectrum resources, it is expected mobile operators will provide prioritised access for public safety services, should PS-LTE be deployed.

Prioritised access capabilities have already been implemented by several operators in their commercial radio spectrum. For example, Telstra in Australia introduced its LANES programme, which enables prioritised access for enterprise and mission critical services. Similarly, BT-EE is providing prioritised radio network capacity to the Home Office in the UK.

Funding challenges
Typically, PS-LTE depends on mobile operators for network resources. The mobile operator business case for public safety can be challenging, even when dedicated radio spectrum resources are allocated. Commonly, network upgrades (such as additional cell sites) are needed to meet the service demands for public safety, but the costs for these upgrades cannot be justified by public safety service revenues. Government funding and in some cases regulatory concessions (FirstNet in the US, for example) are needed to address the mobile operator business model shortfall. Funding challenges are often exacerbated by the fragmented organisational structures and decision-making processes typical of public safety agencies.

Some operators, such as Telstra, have broadened the addressable market for their prioritised network access capabilities to include enterprise and mission critical services in addition to public safety. We believe Telstra’s approach greatly improves the overall business case for public safety, and many other operators will adopt similar strategies in the future.

Since PS-LTE is complex and can be costly to implement, it normally takes significant political will for a country to shepherd its adoption. Unfortunately, this political will has commonly been triggered by disasters, which bring public safety networks into the spotlight. For example, the tragic events of 11 September and hurricane Katrina in the US were arguably the catalyst for the FirstNet PS-LTE network, and the 2014 ferry disaster in South Korea was a strong driver for its PS-LTE network. However, as these and other networks are deployed, we believe they create blueprints for countries to follow and adapt. For example:

• To address fragmented decision making, the Canadian public safety agencies introduced a majority-rules voting system for nationwide technology decisions.
• To assist business model challenges, Telstra’s LANES programme includes both enterprise and mission critical services, presumably to increase market scale.
• To ensure dedicated spectrum allocations are not wasteful, FirstNet allows its mobile operator host (AT&T) to use the public safety spectrum for commercial services when it would otherwise be idle. This also assists AT&T in overcoming the business model challenges that hindered earlier attempts to bring PS-LTE to the US market.
• In markets where trunked radio networks have not been fully amortised, there can be significant resistance to adopting PS-LTE. This has culminated in multi-mode devices which aim to enable a graceful migration to PS-LTE, albeit with the additional cost of maintaining parallel networks.

As countries establish their public safety network strategies, it is crucial they learn from use cases in other markets. In addition, we believe it is important for public safety stakeholders to anticipate the broadband demands in their respective countries and the synergies between public safety and other mission critical services.

By Phil Marshall, chief research officer at Tolaga Research

The editorial views expressed in this article are solely those of the author and will not necessarily reflect the views of the GSMA, its Members or Associate Members.