Private networks vs network slicing

Private mobile broadband networks that leverage shared and licence-exempt spectrum have big appeal for firms that handle sensitive data, but where will the spectrum come from, and could the fledgling industry be crushed once 5G network slicing comes into its own? Sam Fenwick reports

If you are in the two-way radio industry, you may be asking yourself, ‘why should I care about small cells and private LTE networks?’ The best answer is that their level of affordability and ease of deployment may determine the speed at which any transition to push-to-talk over cellular in an in-building context occurs, as John Swarbrick, Andromeda’s founder and managing director, explains. “PTT over cellular hasn’t made a dent in the on-site LMR [land mobile radio] market for many reasons. The big one is the need to pay a monthly subscription to a mobile operator, a cost that doesn’t apply to LMR and quickly mounts up. But equally challenging is poor in-building mobile coverage, variable capacity (particularly for public buildings) and lack of resilience. Wi-Fi doesn’t really solve any of these problems either. I believe private 4G networks offer the solution, but [they need] productising.”

Swarbrick adds that he sees MOTOTRBO Nitro – Motorola Solutions’ private broadband land mobile radio solution, which uses CBRS [Citizens Broadband Radio Service; a 150MHz wide broadcast band of the 3.5GHz band] spectrum, is available via a subscription model, and includes the SLX2000 indoor access point and purpose-built devices such as the SLN1000 – as “the first step in that direction in the US market, but again it’s still at the test licence stage”.

He goes on to say “the big challenge for small cells, particularly in the UK, is spectrum” and that the outcome of the Ofcom Enabling opportunities for innovation: Shared access to spectrum supporting mobile technology consultation “will determine whether small cells succeed or fail [in the UK]”. The consultation is proposing to enable shared access in three bands: 3.8-4.2GHz, 1781.7-1785MHz paired with 1876.7-1880MHz (which is currently authorised to 12 Concurrent Spectrum Access – CSA – licensees on a shared basis through an award process) and 2390-2400MHz (where there are some Ministry of Defence deployments). As of writing, the consultation has already closed and, according to Heli Frosterus, spectrum policy principal at Ofcom, the response to the consultation was originally scheduled for this summer, but may arrive later than that due to some late responses.

It is worth noting here the push at the international level for cellular technologies that can make use of licence-exempt or shared spectrum. For example, there is MulteFire, which unlike LTE-U/LAA can operate solely in unlicensed or shared spectrum without requiring an LTE anchor in licensed spectrum and in the longer term. At the end of last year, the MulteFire Alliance completed Release 1.1, which adds support for eMTC-U (LTE-M in licence-exempt spectrum) and NB-IoT-U, along with additional enhancements and support for additional spectrum bands including the 1.9GHz unlicensed band in Japan, where MulteFire became ready for commercial deployment earlier this year. There is also the news that the CBRS Alliance has completed Release 2 of its specification (which supports a variety of deployment types including private LTE and neutral host) and is now awaiting the FCC (the US spectrum regulator) to authorise wide-scale commercial use of the CBRS band (which is in 3.5GHz) later this year. The alliance has also started work to enable support for 5G deployments using shared spectrum in the 3.5GHz band, with a 5G CBRS service expected to be available next year.

Also on the horizon are Standalone 5G NR-U (5G new radio operating in licence-exempt spectrum) and Licensed Assisted Access (LAA) NR-U, which will require an anchor carrier in licensed spectrum, allowing operators to leverage their existing spectrum holdings with licence-exempt spectrum. Both are being developed in 3GPP Release 16.

David versus Goliath
The future of PMR/LMR is not the only struggle that will take place on the private LTE battlefield. There is also the question as to whether the market will be captured by the traditional telco vendors or whether smaller private LTE network players will be able to carve out a niche of their own. Oh, and of course, there is also the question mark hanging over the extent to which 5G’s network slicing capabilities may allow carriers to compete for the same customers and use-cases using their public networks. Network slicing entails the creation of multiple logical networks – the slices – each with their own distinct quality of service characteristics, such as latency and throughput, and a considerable amount of work on this will take place in 3GPP Release 16, which is currently scheduled for completion next year (functional freeze in March 2020, ASN. 1 in June 2020).

Peter Curnow-Ford, managing partner at Viatec Associates, highlights the scale of the change in mindset and business processes that mobile network operators (MNOs) will have to undergo if they are to realise their ambitions of generating additional revenue from the enterprise and vertical markets with 5G, given that at present the vast majority of their activities are set up to handle services that are billed monthly and are bundled with handsets, while the billing mechanisms and commercial arrangements around the provision of network slices may be very different. For example, would a vertical user be willing to pay for the data they consume if they are using a network slice as an alternative to a private LTE network which wouldn’t require them to do so?

He adds that this change in approach will require a great deal of additional staff, especially to deliver the necessary 24/7 support that may be required in many cases, and many of the devices in question will use embedded sims (e-Sims), which come with their own set of challenges for MNOs. Curnow-Ford highlights the importance of system integrators in any attempt to bring the benefits of the latest wireless communications technologies to vertical industries as they have been acting as ‘translators’ for many years between the technology vendors and the end-users, to whom our jargon can feel like something of a foreign language.

He also notes that part of the appeal around network slicing from an MNO’s perspective is the way in which it allows an enterprise’s IT team to be able to change, adapt and fine-tune the connectivity they are relying upon, using a cloud-based dashboard, without giving them the ability to make changes to the operator’s network in an unconstrained way.

During a recent Cambridge Wireless event entitled ‘Are small cells ready for private LTE primetime in the lead-up to 5G’, Caroline Gabriel, chief research officer at Rethink Technology Research, said: “In theory, network slicing should get rid of all the need for private [networks], but you still see that every single vertical, and even some use-cases within those verticals, have a different set of partners, of deployers – there’s still going to be a lot of physical stuff that has to be done. [Both] the MNOs and some of the big vendors like Ericsson and Nokia find it hard to scale down to do enough diversity. [While] I’m a believer in slicing as a platform and the technology [at] some point, there’s still got to be people who deal with the regulations and the industry partners and the civil works, and the MNOs or [the] big vendors are not going to want to do that for every sector, they’ll pick a couple of big ones. It will change with slicing but it’s almost like the [cloud]. AWS being there and supporting a million things on its cloud doesn’t stop specialists going into enterprises.”

Speaking during the same panel discussion, Tadhg Kenny, Druid Software’s SVP – business development – marketing, said systems integrators, which often are where opportunities for his company begin given their ongoing relationships with end-users, “can deliver a solution [and] the MNOs just aren’t that beast at the moment, they’re not a systems integrator as I would know it delivering those kind of telecoms solutions, [but] maybe they’ll evolve that way”. He added that while Druid constantly engages with MNOs (and without wanting to tar them all with the same brush, some divisions, within some of them, are moving more quickly), “they’re very slow to adapt and to move and their roadmaps are years in advance” and are generally shifting at less pace than systems integrators, mobile virtual network enablers (MVNEs) and MVNOs.

Kennedy also stressed the importance of fixed wireless access, particularly for rural broadband, and LTE mesh, and while the latter has been deployed in public safety and the military, it may also have a role in allowing private LTE networks to link together to cover wider areas. In his presentation, he also highlighted private networks’ suitability for hospitals, elderly care facilities, harbours, oil and gas, utilities, enterprise hospitality, manufacturing, and public safety (see box), through discussing a number of the company’s deployments. Speaking of public safety, Global Market Insights has predicted that public safety applications will account for 35 per cent of the private LTE market by 2024.

Nick Johnson of ip.access weighed in on the discussion as to whether private networks will be disruptive, saying that his company “embarked on this private network journey in the hope that we could get the MNOs out of the way [and sell] infrastructure directly to end-users who could see the value of it rather than seeing it as a cost”, given MNOs’ interest “in the dollars they can shave out of capex. I have a nightmare that having got the MNOs out of the way, we then usher in a new generation of service providers… the Industry 4.0 – some other group of equally staid and conservative organisations. Are we just going to replace one set of overlords with another and end up with a completely undisrupted industry?” He added that while he believes “small cells are ready for prime time in private networks”, he is afraid that “innovation will be stifled out of the supply chain by the same old forces”.

Switching scene again, this time to an Ofcom wireless innovation event, Derek Long, head of telecoms and mobile at Cambridge Consultants (the company that developed the wireless system for Ocado’s robotic warehouse), said private networks are a good solution for geographically focused areas such as campuses or factories and added: “The BMW factory in Oxford, for example, produces about a thousand Minis a day. If the average selling price of a Mini is £20,000, it will generate £20m revenue a day. The decision to outsource manufacturing technology for a scenario such as this, which holds such a critical role, is high risk for both the manufacturer and the service provider. In such a scenario, a private network may make a lot of sense. On the other hand, when the vehicles are on the road, there may be a manufacturer’s requirement for nationwide coverage. For example, providing services or software updates, regardless of the vehicle location. In this case it may not be feasible for a company to have its own nationwide network, so a dedicated network slice could be the most practical solution. I don’t see private network/5G network slicing as a dilemma, I expect high performance connectivity in private and wide area networks to work hand-in-hand, each focused on solving a different challenge.”

It’s worth noting here the great extent to which both Ericsson and Nokia are targeting the manufacturing sector with combined private networks/Industry 4.0 offerings, as seen most recently by Nokia displaying its Factory in a Box 2.0 at Hannover Messe in early April.

Long’s fellow panellist – Guillaume Sampic, enterprise strategy director at BT – added that scenarios requiring national or international roaming are less tolerant of any divergence from cellular standards than very local applications.

When it comes to private LTE and public networks, it is possible to have both running over the same infrastructure but logically separated, and with the neutral host model it is possible to support more than one MNO, while still providing a private LTE network. Druid Software and Washington State’s Geoverse have teamed up to pursue this approach in the US. The latter, a self-described enterprise mobile operator, will use Druid’s software to deliver this using CBRS spectrum.

While at the MulteFire Alliance’s open day at Mobile World Congress Barcelona, David Orloff, chair of the Small Cell Forum, said (while discussing enterprises’ use of private networks): “We all know that these [CBRS] networks are meant to be shared. [If enterprises] have a neutral host need, they’re pushing for CBRS in the US or equivalent bands in France and Germany.” He added that MNOs are changing their views on private networks – “a couple of years ago, operators were totally against private LTE, but now we’re really starting to see that shift because” if they were to provide enterprise and industrial customers with private LTE networks, this gives them captive customers to whom they can then sell additional services such as IoT and multi-access edge computing (MEC).

While a good chunk of this article has focused on private LTE versus network slicing, there is also private LTE versus Wi-Fi (it will be interesting to see how Wi-Fi 6 affects this). One of the private LTE projects that we have previously reported is Group Air France-KLM’s work to move both its voice and data services to a single converged network, which was partially prompted by issues with using Wi-Fi in areas with large amounts of metal and an ageing TETRA network. Look out for more on this once the French regulator allocates spectrum for private LTE in 2.6GHz TDD.

So, the outcome of the future struggle between private networks and network slices may hinge on the ability of the new would-be disruptive players to scale up and the extent to which MNOs are willing to scale down – extending their reach into smaller organisations and verticals. Going by Long’s comments, it may be that network slicing will come into its own where regional or national coverage is required. System integrators clearly have a huge part to play and may end up wielding considerable influence when it comes to deciding which option end-users select, while the existence of the neutral host model means that, at least in some circumstances, it is possible for everyone to win.

A hot start
Let’s make this topic less abstract with a look at a private LTE deployment. Tyne and Wear Fire and Rescue Service (TWFRS)’s new command and control vehicle (shown below) has a dedicated private LTE network, which covers a five-mile area, is quick to set up and supports real-time, high-definition video streams from body-worn cameras, drones and four deployable point-tilt-zoom (PTZ) cameras, two of which are thermal. Images are streamed into the command vehicle, and anywhere within TWFRS. The overall solution was a collaboration between Bence Command, which designed the vehicle and the network’s simplified user management system; Druid Software, which provided the ePC LTE Core software application and worked with Bence from the project’s conception to bring the solution together; ip.access, the provider of the LTE base station hardware; and CellAntenna Corporation, which designed the antenna system.

One of the first incidents it was deployed to last year was a large waste fire at a disused recycling plant in Sunderland, which took a week to extinguish. The vehicle was used to co-ordinate 10 fire engines and 54 firefighters, and liaise with the Environment Agency, Public Health England and Sunderland City Council, and its drone was used to provide real-time aerial views of the fire.