Making the most of public-safety communications investments

In 1928, the Detroit Police Department became the first user of land mobile radio (LMR) for communications between patrol cars and dispatch centers. Since then, radio communications have become indispensable to public-safety agencies, especially to first responders sharing real-time, tactical field information.  Now public safety administrators face the challenge of maintaining their deployed radio systems while at the same time embracing the latest technology and preparing for the future. With tight budgets, increasingly sophisticated needs and rapidly changing technology, how do municipalities ensure that their investments in communications infrastructure will continue to provide value for decades to come?

The changing technology landscape

Momentous changes in public-safety information and communications technologies are ongoing. Advancements in digital signal processing and antennas have significantly improved radio communications. For over 80 years, analog, vendor-specific LMR systems have supported mission-critical voice communications. In the 1990s, digital LMR standards, known as Project 25, were developed to enhance communications interoperability. Many public-safety agencies are adopting the more advanced digital systems that incorporate enhanced voice and data services, such as GPS location, text messaging, metering and encryption. The new radio systems allow multiple, discrete conversations on a single frequency channel, enabling better voice quality, higher spectral efficiency and longer radio battery life.

With the imminent buildout of the FirstNet public safety LTE network, wireless broadband access will be available to first responders anywhere they need it.  Agencies experimenting with bandwidth-intensive applications such as drones and high-definition mobile video  will require dependable connectivity to reliably deliver real-time information.

From now to 2040

As the frequency and sophistication of security threats rise, public-safety agencies must modernize to protect citizens. But with existing LMR's massive investments and extensive coverage, any new backhaul network must be interoperable with those older systems and ready to support new applications such as LTE radio, drones and high-definition video. Consequently, officials also must be able to scale the network's bandwidth capacity by adding new microwave and fiber trunks to deployed radio site routers without going through a forklift upgrade and disrupting critical connections.

These new networks also must be able to become automated, programmable and intelligent in order to respond to changing situations. Therefore, readiness to usher in new networking technology such as software-defined networking is crucial.

All of these requirements can be met reliably and efficiently with a backhaul network that utilizes Internet Protocol/Multiprotocol Label Switching (IP/MPLS), which is already deployed today in many new public safety networks worldwide. It features these specific capabilities:

A wide range of communications interfaces: As different generations of radio technologies use different communications interfaces, the edge router must have a wide interface range support, from 4-wire E&M voice signaling to modern Ethernet. Full interoperability with analog and P25 LMR, as well as LTE systems, is pivotal.

VPN services: Support of multiple generations of radio technology, and other applications such as CCTV and access control systems, requires different communication services.   These services, which include everything from point-to-point TDM transport to the full range of IP-based virtual private networking services, must maintain complete application separation to ensure performance and security. VPN services can further expand to support other city services and new applications as they emerge.

Scalable network capacity: Flexible and graceful scaling through increased microwave channel throughput by using higher-order modulation scheme, packet compression and cross-polarization interference cancellation.  Networks must be capable of expanding  microwave link capacity, migrating from microwave transmission to optical fiber when justified and ready for an optical gigabit Ethernet link up to 100 gigabit/sec when required. As the backhaul network carries critical traffic, it is imperative that the scale-up not affect critical connections.

Future-proof network: As network capabilities evolve, a programmable, automated and intelligent network can support  new public safety communications needs. Looking even further into the future, the IP/MPLS backhaul network will remain an integral component of a future 5G public-safety network.

The bottom line? Given tight public-safety budgets, it is crucial that current deployments can be used for 20 years or more. In the face of rapid technology change, investing in an IP/MPLS future-ready network is the smartest way to bridge the past to the future while helping to assure the best return in functionality and innovation over time.