How Public Safety Networks Become Public Networks with a little Network Slicing

By Mika Skarp

There will be never enough available radio frequency spectrum for our expanding mobile networks, and finding new frequency opportunities is getting harder and harder. It’s a finite resource.

One way to gain access to new frequencies is via public safety networks. And before you scream “Fire in the house, they want our spectrum!”, take a look at some of the key 5G innovations that will make that possible and without risk to public safety.

TETRA networks, or Terrestrial Trunked Radio (and formerly Tran-European Trunked Radio as first written into a standard in the mid-nineties, but only saw large scale global adoption in the 2000s-2010s. Designed to provide a dedicated, failsafe, and more secure network communications for police, fire, ambulance, military and other first responders, TETRA quickly took off pretty much everywhere. Everywhere except the U.S. that is.  It was only in 2012 that the FCC elected to permit TETRA networks in the US with the caveat that it could not be applied to public safety spectrum, and was generally only used for transport applications.

TETRA uses TDMA network technology to provide a range of public-safety specificapplications going far beyond standard one-to-one communications to provide for one-to-many and many-to-many cellular communications. Other advantages include more stable lines, and longer signal range, (thanks to the use of lower frequencies in the range of 8-150 kHz). On the downside, TETRA networks, in their current configuration, are slow, costly to maintain and generally seen as a waste of much needed radio spectrum. There’s no doubt that these safety-essential networks are in dire need of an upgrade, but may well need to be re-thought entirely to allow business and consumer users and accommodate the arrival of 5G.

What may seem a radical idea – sharing once dedicated public safety networks with the rest of us – becomes less so when we consider the many advantages of modern, sliced TETRA network could deliver for public safety. Just like the rest of us, public safety users have increasing need for broadband data connections. This has been taken into account in LTE standardization, with very solid Quality-of-Service guarantees and capabilities.

LTE also offers a full set of public safety-specific features, like push-to-talk and group call options. To date, these public-safety essentials and even consumer-friendly features have not been widely used over the past decade of 4G LTE. One reason for this is that access to these features has been technically difficult, but also, and perhaps more importantly they have been lacking a business model to support them.

FirstNet the First Responder Network Authority in the U.S. provides a great example of how the needs of public safety and consumer and business applications can co-exist safely and harmoniously in a single sliced network. Along with its technology partners, including Cloudstreet, FristNet is in the process of standardizing, and soon rolling out, anew kind of network built around the public safety feature set but also providing commercial services that will allow transport, shipping and post services some of the same public safety features.

The advantages of combining public safety and commercial users and applications within the same network are significant. First, is the ability to dramatically reduce the costs of network rollouts while increasing capacity and performance for a range of buyers, including the private sector.  At a time of shrinking cap ex budgets for infrastructure, allowing carriers to create cost efficiency and drive new revenues is critical.  From a user perspective the advantages are just as enormous. While public safety users will always be assured state-of-the-art technology, in their hands and on their heads, consumer and business users will enjoy a range of never-before used and very practical features. Most importantly, our networks will be better equipped to deliver essential safety features to all users.

Of course there’s concern about the possibility of network congestion in emergency situations. But here the ability to deliver application-aware network traffic management enabled by Cloudstreet eliminates that issue. As a result these networks will not are not only faster but also be much more reliable backed by rock solid SLAs.

As an early adopter of these innovations ,the U.S. and FirstNet are paving the way for similar developments in Mexico, Canada and Northern Europe. In parallel, Britain and Korea are developing modern hybrid networks along similar lines. No doubt it’s an exciting time for network architects and with public safety as a key driver, I believe that this will be one of the first use cases to demonstrate network slicing and especially SLA-assured network slicing on a large scale.