A debate is currently raging in the telecoms world which many of us are not aware of: Do we need dedicated networks for public safety services? The debate is literally life and death.

When this is added to the normal commercial pressures of the high stakes communications world, the arguments take on a much more personal meaning and lead to much more firmly held views.

There are entrenched industry positions on the Public versus Private Network debate. And indeed the users of Public Safety services have every reason, historically to support the Private network model to ensure operational performance under the most severe conditions.

Likewise the ever-evolving public networks have moved on a long way from the bad old days of analog and then first generation digital mobile phone infrastructure. It might be said that these entrenched positions are more about legacy networks and history than they are about rational technology based solutions.

Let us consider where we are today.

  • There are a few basic truths driving the evolution of the use of radio spectrum.
  • The amount of spectrum is finite and increasingly it's in demand for high value applications. The demands for personal mobile communications enabled by mobile phones, tablets, phablets and laptops, and now increasingly machine to machine communications or the so called Internet of Things.
  • The bandwidth per personal device is growing rapidly driven largely by video and rich applications that need regular updates for example.
  • The numbers of devices is exploding as well as the cost effectiveness that is introducing a huge variety of new devices such as sensors and other forms of embedded computing.
  • All networks are becoming Internet Protocol (IP) networks - both fixed and wireless. Today fixed networking is all IP and mobile networking will migrate to all IP through the deployment of 4G or LTE. When the older 2G and 3G networks are finally retired there will be only IP remaining for all forms of communication both voice and data alike. Furthermore as 5G is standardised and matures, an all IP environment will facilitate network-controlled seamless handover from one network to another, optimising the effective use of all the available networks with application awareness, a big subject in its own right not covered further here.

Another interesting factor in this debate is that the US federal government recently decided to fund a nationwide LTE network specifically for the uniform use by Public Safety Service Providers. This is an NBN scale initiative with as much political debate attached. Furthermore the regulatory reform needed to see this initiative eventuate is significant. In the meantime the debate rages about this and other public versus private models and will probably take a decade to eventuate.

Some of the problems that need solving are complex and includes:

  • Poor existing networks that are becoming too old and inadequate for the modern needs of all Public Safety services as more bandwidth and coverage grow in importance.
  • The backward compatibility of new video enabled solutions needed for today's and future services.
  • Available spectrum is all over the place with different countries allocating different spectrum for these services and often not contiguous. That limits the ease of use.
  • New network technologies are allowing much more performance and flexibility as well as efficiency.
  • Telecommunications Carriers are building major new networks leveraging 4G technology, arguably with sufficient capacity for Public Safety services as well as their own service demands.
  • During emergency situations the public networks today get congested and do not lend themselves to the high demands during critical events, just when performance is demanded.
  • Legacy systems continue to deliver at least some capability and Public Safety services funding is patchy at best and often inadequate.
  • Each Public Safety agency has a tendency to do their own thing, further reducing efficiency and limiting operational integration.

So where does the answer lie?

From a purely technical perspective it can be argued that a common public LTE network is capable of doing it all. With IP layer network partitioning and new network sharing and tariffing models in place it would be possible to protect capacity for Public Safety services and it would also be possible to dynamically allocate capacity where it is needed to service the needs of any situation providing there is network coverage and of course if there was only one network then it would be far easier to fund much more extensive coverage. This of course is easy to say as an engineer but almost impossible to imagine actually happening.

There is an entire industry immersed in ensuring that the Public Safety services continue to operate independently of the public networks and have some very strong arguments that drive the position. Issues such as the need for redundancy and separation for national security and public safety reasons are very emotional and historically very significant.

There are some impressive technology advances that can and will be leveraged for the Public Safety services market. In general these advances are simply taking advantage of the ever-increasing computer processing performance that is met with ever-decreasing costs.

  • Software controlled beam forming, a technology that CSIRO boffins have been working on for a number of years is now being commercialised. This technology offers some very useful capabilities. So what is beam forming? An intelligent base station with a circular array of dipole antennas can, under software control, transmit a very narrow beam directly towards a remote device while simultaneously reusing the same spectrum in several other beams to other devices all at the same time. So a base station can find, then establish the beam and continue to follow the remote terminals while they are moving, with full bandwidth available to each terminal. This software is independent of transmission frequency and bandwidth and so can be used in many different situations. One of the very nice things about this approach, beyond the obvious spectral efficiency, is the ability for the terminals to be very quickly found and links established with no complex alignment or setup time. This is a great advantage for an emergency situation where field operations need to be deployed rapidly under high stress conditions.
  • As has already been discussed, spectrum is all over the place. With advanced software controlled radio, random non-contiguous bands of spectrum can be easily combined within the digital radio to build up enough spectrum to support the bandwidth required to support the services demanded of the particular emergency. With modern radio transmitters and receivers operating across a broad band, spectrum can be easily combined from the UHF and VHF bands for example.

Another interesting side effect of this sort of technology is that one could now challenge the way spectrum is allocated by the authorities tasked with managing it. With spectrum reuse and beam forming, it could be argued that a new model for event and geographic based spectrum allocation could be considered making spectrum a more flexibly shared resource than the current permanent allocation models.

The bottom line

While the public versus private debate continues, the opportunities exist for more private networks and more incumbency that further embed the old model so regardless of the elegance, efficiency and quality of the IP enabled technologies it is highly likely that unless or until the emergency services sector actually fails to fund their most basic needs they will continue to support the old fragmented do-it-yourself model while spectrum management and price will remain a major element for this ever increasingly congested spectrum management challenge.

Mature and sophisticated IP networking now really does support the robust network segregation; application based quality of service and can be architected to deliver all the necessary availability, ubiquity and performance. But, as always, the operational needs of the day will make it very difficult for both public and private network operators to migrate from one model to the other.

Perhaps it's time to take a fresh look at the regulatory position and policy settings that might be improved so that new technologies can be leveraged to deliver the next generation of cost optimised, high performance, ubiquitous services for all Australians, all the time that ultimately can provide basic utility as well as save property and lives.