France's push for public safety broadband

France’s work to transition to mission-critical broadband is well under way, with much of the initial conceptual work complete and the first wave of commercial partners on board. Sam Fenwick summarises the state of play, with the help of the Ministry of Interior (MoI).

Our story begins in 2015, with the Charlie Hebdo attack in Paris (which left 12 dead) on 7 January and several related incidents that took place between then and 9 January. The latter include the Hyper Cacher kosher supermarket siege, which cost the lives of four Jewish hostages and the attacker, and the Dammartin-en-Goële hostage crisis, which occurred when the Charlie Hebdo attackers were located following a manhunt, took hostages at a signage company and then were killed when fleeing the building.

Three different forces were deployed to deal with these attacks, each using a different radio network. It proved difficult to co-ordinate the response to two attacks occurring at the same time with this approach, and those dealing with them felt the absence of the ability to share videos from the field.

To address these issues, three overarching principles were decided – that every force should use the same interoperable networks, and that these should allow the use of broadband data and video services and must use standard technologies. The PCSTORM project, the MoI’s response to the difficulties encountered in 2015, seeks to develop a tactical PPDR network for special forces that uses standard LTE technology. It was launched in 2017 and contracts were signed with the project’s first six vendors in 2018. The different lots are as follows:

Lot 1 (tactical networks and terminals): Athonet – local delivery of this lot will be handled by Telespazio France, the French subsidiary of Telespazio, which is part of the Leonardo and Thales groups

Lot 2 (SIM cards): Gemalto – this includes customised SIM cards, eSIMs and subscription management solutions

Lot 3 (access transport network): Orange, which will provide the radio access network (RAN) over a wide area for the PCSTORM project with priority and pre-emption and ensure that other French commercial mobile networks can be used as a back-up

Lot 4 (applications and services): StreamWIDE – the company will provide MCX services over LTE, using its Team On Mission platform

Lot 5 (MCPTT-PMR gateways): Prescom – these will ensure continuity of voice and data services between users of narrowband networks and those equipped with PCSTORM solutions and will allow the Ministry to enable interoperability between a variety of heterogenous networks for all French national security forces.

Lot 6 (integration/consulting): Cogisys

Lot 7 (resilient infrastructure): as of writing, this has yet to be awarded, and the MoI is seeking to do so in July 2019.

It is worth noting that StreamWIDE and Prescom jointly demonstrated interoperability between LTE MCPTT broadband networks with narrowband networks such as Tetrapol, P25 and TETRA back in 2017, based on an operational scenario of a terrorist attack in a large railway station.

This year, the plan is to see the first tactical bubbles open for operational service, with the dedicated frequencies for tactical networks in place by July.

The network of tomorrow
However, the wider vision is to have a nationwide LTE-based network – the RRF (Réseau Radio du Futur/ Radio Network of the Future) – that will include the tactical bubbles pioneered by the PCSTORM project (for additional resilience and capacity where/when required and aided to a limited extent by some dedicated state-owned infrastructure, especially for Paris and The Petite Couronne) and will be able to take advantage of new technology such as 5G, as and when it becomes available. The programme was launched in 2016 and is pursuing a hybrid model, which will make use of commercial radio network infrastructures, with the MoI operating the mission-critical services that will run over the commercial networks. “We think that self-owned infrastructure is a past model,” adds Bruno Chapuis, the MoI’s deputy head of mission for the RRF. He also says the first level of resiliency will consist of dynamic national roaming, together with priority and pre-emption for mission-critical users.

Aside from the desire for greater interoperability and functionality, the RRF programme has arisen because of the country’s ageing Tetrapol networks (RUBIS – the nationwide network for the French Gendarmerie; and INPT, which is used by police, fire brigades, emergency healthcare services, customs, defence forces, mobile gendarmerie, authorities and for prisoner transfers); as well as this is the need to have robust and modern public safety communications in place ahead of the Rugby World Cup in 2023, along with the Olympic Games and Paralympic Games, and the opening of a new line on the Grand Paris Express in 2024.

“The Tetrapol ecosystem is rather small and from the last century; that is why it does not fit all the modern requirements,” says Chapuis.

The MoI seeks to bring blue users (police and gendarmerie) onto the RRF network in 2020-2023, with the migration of red users (firefighters) starting later in the same year and that for white users and other users (such as emergency medical services, forestry) beginning in 2021. Chapuis adds that the aim here is be ready one year before the Olympic Games.

He explains that today, France has around 150,000 terminals for PPDR users in circulation, but as these are used in a pooled manner, they meet the needs of roughly 300,000 users. However, “our objective is to be at the level of Germany and we would like to have all the military people, customs officials, metro users and so on on the RRF network. So our aim is to have around 700,000 users.”

The shape of things to come
Emmanuelle Villebrun, lead technical architect of the RRF at the French Ministry of the Interior, provides us with a look at some of the long-term thinking around the RRF, particularly how it may be able to use to its advantage some of the capabilities that will come in 5G. It is worth noting here that as she is responsible for phase II of the RRF (Phase I is PCSTORM, with Phase II consisting of purchasing tactical networks as a service from a commercial operator, which will use their spectrum) and no final decisions have been made, her comments reflect her current thinking and priorities and are proposals, rather than MoI policy.

Villebrun says the main contingency being considered in case of widespread and long-lasting power cuts will be the combination of tactical networks and satellite backhaul, as the batteries for the former will use batteries on board vehicles.

“The idea is to have opportunistic backhaul, if the MCPTT service can use any IP pipe, it could be fibre, Wi-Fi, a part of the MNO network or satellite – we hope that with satellite backhaul we increase the availability and the coverage, but you can do it over the Wi-Fi, whatever you have.”

She highlights the work being done in 3GPP to provide a 5G-based integrated cellular component for satellite services, and adds that part of the rationale for investigating the use of satellite is that “in France, the rural carriers are financed by the government” and the operators do a lot of radio access network/site sharing, which reduces the availability/resiliency benefits associated with dynamic national roaming.

Villebrun adds that as the cost of a dedicated satellite service for France’s public safety sector would be cost-prohibitive, a service that works across all verticals and operators would be preferable. She expects to have a clearer view of what the satellite industry can provide (especially in terms of availability) in 12-18 months’ time.

The RRF is intended to have multiple layers of resilience, while also providing PPDR stakeholders with interoperable mission-critical communications

“We recently launched a request for information (RFI) about licensed shared access [LSA – a spectrum-sharing method similar to CBRS in the US],” says Villebrun. She adds that the initial responses from the French MNOs stated that if they were to allow the MoI to [hire/rent] their spectrum to allow the use of tactical bubbles, they wouldn’t make sufficiently high margins for this to be of interest. However, “they are looking at providing us with tactical networks as a service… this is under investigation and we have consultants working on it and we will publish the results”.

The RFI covering LSA, which was issued in September 2018, also requested information on air-to-ground communications with LTE, and the programme issued an RFI on direct mode in October.

Villebrun adds that the MoI is currently studying the idea of buying a service from MNOs that will serve a specified number of “communications per square kilometres” with voice and video services, with a stipulated level of resilience, and this could be in the form of a secure virtual network (thanks to 5G network slicing), backed up with service-level agreements between the MoI and the provider(s). The idea here is it would be up to the provider to deliver the required service and that this approach would avoid the development of bespoke technologies and allow the MoI to avoid having to go into “the technical detail of the radio interfaces”.

In terms of cost, Villebrun says the MoI is seeking to achieve a price per user that is “quite near” to a commercial subscription, with some additional costs for resiliency on top, which would be minimised through network sharing. “We would also like to have very cheap terminals, so off the shelf...”

She notes that the timetable for RRF has yet to be decided and the team is assessing the feasibility of widespread deployment in 2022. However, one objective is to have as much of a mission-critical broadband service as possible prior to the Olympics.

“I would like to see the opening up of the indoor coverage market,” Villebrun says. “We can’t pay for dedicated in-building coverage for public safety, we should share the costs with e-health – ie, hospital at home, surveillance to allow elderly people to remain independent for longer, which requires indoor coverage and public coverage, small cells or whatever. We need to build something in common with those new markets and we hope that those markets will push the in-building coverage which we will be able to reuse. More and more indoor coverage is being added, in fact. We hope that the regulations around 5G will allow more in-building coverage. These are being discussed, but with 5G we expect there will be opportunities.”

She adds that the feedback from the PCSTORM project has been positive and that the end-users are “quite enthusiastic and waiting for the [tactical network] service, and the fire brigades also want to join the system. The concept of the tactical network, replacing long-range proximity services and long-range direct communication, is under assessment – the remaining issues are control room and video. In the current contract, we have a certain amount of video but it’s a little bit better than best effort. We have no warranty of service for massive/mission-critical video.”

The art of push-to-video management
Villebrun and her team see video as the “next killer application”. She highlights the many mission-critical video functions that were introduced in 3GPP Release 14 and notes that if there is a massive response to a huge attack or a very large planned event and everyone presses their push-to-video button, with PCSTORM “we don’t have any feedback about such circumstances and [will] have to be careful”.

Similarly, there needs to be some way in which the videos being transmitted can be prioritised, as the video service cannot be allowed to consume all the network’s resources – “We need to prepare operational staff so they can make choices in case of crisis, because at some point resources will be limited.”

Villebrun is leading a TCCA Critical Communications Broadband Group (CCBG) taskforce to investigate the practical considerations around the use of mission-critical video (MCVideo). She sees video analytics as the next step to consider once control of video streams and how this works operationally has been determined and well established, and she highlights the potential for video analytics to be done in a distributed manner, using “multi-access edge computing which is an ETSI standard – there will be a lot of things that will be possible with video in the future if it’s well implemented”.

Villebrun highlights her concerns around the cost of devices that use Band 68, especially as the MoI would like to provide volunteer firefighters (who have never been issued with Tetrapol terminals) with a relevant level of service, which necessitates very cheap terminals, with bring your own device (BYOD) being an option and the cost of each subscription targeted at around a few euros per month.

Clearly, a great deal of thought and effort has been expended to get both PCSTORM and RRF to their current status. While the project is benefiting from the experiences of its peers (such as the ESN and FirstNet projects in the UK and US, respectively) and made the wise move to embrace open standards from its inception, it will be interesting to see how it copes with the hard deadline created by the Olympics Games, as the degree to which ESN has overrun has highlighted the difficulties in delivering such complex and mission-critical projects.