Virtualization is key
Deployment of network functions virtualization (NFV) and implementation of software-defined networking (SDN) are designed to deliver flexibility. NFV enables network resources to be spun-up when they are needed, allowing CSPs to move away from using over-provisioning as a quality safety net and obtain a tighter control over costs by using network resources more efficiently. Coupled with the separation of the control and data planes in SDN, operators have the potential to flex, adjust and control the network in almost unlimited ways.
CSPs have talked about NFV and SDN for a decade, but deployments in the mobile environment, where flexibility in the network wasn’t a particularly useful tool, have been limited. 5G changes that completely with virtualization going from being interesting to essential for CSPs looking to bring the full 5G vision to life. But it’s only one more step.
Like virtualization, mobile network slicing is a concept that’s been around for some time, but it has new purpose with 5G. While slicing is possible on 4G networks, 5G makes it a much more viable and useful concept as performance potential almost demands to be divided and targeted. Furthermore, the new 5G core network is designed to support multiple slices, something that will be essential to commercializing the benefits. The new core also enables more usable 4G slicing, which was not lost on our CSP respondents. A large majority said they plan to use 4G and 5G slicing.
Slicing benefits both sides of the 5G business case by increasing the potential for revenue creation and improving cost efficiency. In a study conducted by BT and Ericsson, slicing delivered a 40% savings on operational expenditure (OpEx) compared to a single big network, illustrating the potential for efficiency. However, for maximum benefits operators should be looking at many slices not just a few.
How many slices?
The number of network slices operators should be aiming to support is anything but certain. Half of CSP respondents and nearly as many supplier respondents admitted to not knowing, and this is perhaps the most telling statistic from this question and perhaps the entire survey.
Suppliers are slightly more bullish about the development of slices, with 10% anticipating slices in the thousands. Converged operators were the CSP group expecting to deploy the most slices. On the supplier slide, systems integrators were the most conservative, perhaps because they understand the complexities of supporting multiple slices but have no great vested interest in supporting the proliferation of slicing.
The conservative views of the number of network slices CSP expect to deploy is somewhat contradicted by CSPs’ and suppliers’ understanding of how many vertical markets need slices; all but mining and education were identified by more than a third of respondents. This suggests that CSPs expect to need slices to target vertical customers, and given the number of verticals and the vast array of possible use cases within those verticals, we can assume that more rather not fewer slices will be required.
Slices for use cases
When you drill down into these verticals, a single slice would not be enough. For example, connectivity to cars will be used for many different things (performance monitoring, traffic flow information, insurance driver data, entertainment, dash cams live feeds, not to mention autonomous driving), and some may require or become more economically viable using separate slices. The same is true for smart city, healthcare, government and manufacturing.
At Mobile World Congress 2018, Andreas Mueller, Senior Expert and Project Manager, Bosch, claimed that Industry 4.0 is the “killer app” for 5G, but he was equally adamant about the need for slicing: “We need use case slices or it [5G] is useless.”
This will be the second great challenge for 5G: Once the networks are deployed, how will CSPs deliver by use case and possibly by customer?
For many CSPs, the per use case/per user approach to slicing is too far in the future to discuss sensibly now, but BT has invested significant time and energy into investigating the potential of slices. Maria Cuevas, Head of Core Services for the company believes that the number of slices will grow incrementally from a few to many over time but that not every service deployment will need a slice.
“Every time service providers need to deploy a service we must ask ourselves what the right approach is,” she says. “Can that service can be supported by the network or added to an existing slice, or do we need a new one?”
Operational transformation is required
Ultimately 5G NR, virtualization and network slicing represent the foundations for flexibility and for delivering the 5G vision. However, while they solve many problems and make service differentiation not just possible but desirable, they also pass huge challenges and complexity onto the systems and processes responsible for operating them. This begins with transforming these technologies into services, which is examined in detail in the next section.