
Alla Goldner, Director, Technology, Strategy & Standardisation, Amdocs, says effective, top-down and end-to-end slice orchestration and management could revolutionise mobile network operators’ business models. Here are 7 Things Goldner knows about that revolution – from slicing’s phased introduction to the end goal.
1. Network slicing in 5G is not new, but it is different.
Network slicing is not new as a concept specific to 5G. It was talked about in 4G, but 5G is the first time we have a standardised definition of how a slice should work end-to-end in the network. This means that you can build a logical network consisting of different network functions and define the service parameters – bandwidth, latency, security and so on – that are required from each function within that slice.
Service providers can offer this capability up to enterprises, which gives them a new means of differentiation. In that sense, service providers can compete with webscale providers like Google, Amazon, Microsoft and so on; providing services but in doing so actually ensuring those end-to-end requirements.
2. The introduction of network slicing will be phased.
The way service providers introduce network slicing will be a phased process. The first phase will be about using slicing to define internal network optimisation – where certain slice classes are used as a means of gaining network efficiency. These slices will not really be tailored for customer requirements.
The second phase will be more about introducing slices that have specific service-related requirements, where customer segment slices are created with optimal parameters for that service. For example, an IoT slice with low latency, or an eMBB (enhanced Mobile Broadband) slice with guaranteed high capacity.
The third phase is a more advanced level of network slicing. This is a level of slicing where service providers can provide enterprise customers with the ability to order and manage their own service requirements. This is where we see the full advantages of network slicing coming in: service providers provide parameters such as capacity, latency, security as generic requirements to the enterprise, but the enterprise actually tailors additional services as a service chain on top of those capabilities and builds out its own slice end-to-end.
3. An end-to-end management capability will be key to this phased introduction
Slicing obviously needs to be supported by the network functions themselves within the 5G RAN, transport and core networks, with functions supporting slicing principles as defined by 3GPP. But for any end-to-end approach to succeed, this whole thing needs to be managed in a holistic, end-to-end way.
So, the first phase of that holistic approach is slice preparation, which includes design and onboarding. The second phase is about managing the life-cycle of a network slice, which means the creation, activation, reporting, assurance and monitoring of a slice, being able to amend a slice in closed loop operation. Finally, there is the decommissioning and termination of a slice. For all this you must have network management that is based on clear end-to-end visibility into whatever exists or is defined in the network.
4. This end-to-end slice management crosses previous domain boundaries
The important thing here, and this goes a bit beyond standards, is that the whole slice management process needs to start from the top – from the definition of the service, or an order request from a customer, all the way down through different VNFs/PNFs/CNFs from different vendors. This is why we in Amdocs couple the BSS and OSS functions along with NFV slicing management functions and provide a single offering where we include ordering and charging per slice into the overall slice management offering.
Network slicing means that for the first time the need for an end-to-end network management solution is clear, justified and a must.
What was preventing full end -to-end network management in previous generations were claims from the traditional VNF vendors that their VNF Manager (VNF-M) can manage their VNF instances and chains, and that this is sufficient. With network slicing that is not sufficient. Service providers do not have the same vendors in the RAN, core and transport domains, and so even if one vendor comes with its own VNF-M or even NFV-Orchestrator (NFV-O) then that must still be connected with the end-to-end solution with full visibility, again, to assure end-to-end holistic management for the different parameters required per slice.
Network slicing means that for the first time the need for an end-to-end network management solution is clear, justified and a must.
5. We now have a picture of how to manage network slicing, in this holistic way.
We understand the “how” of network slicing. By now, pretty much, we can build a map of that slice management journey. On the top there are some vertical industry organisations such as automotive and manufacturing industries which are trying to bring use cases into the industry, defining their requirements. Then there are industry alliances such as the GSMA, NGMN, TMForum and MEF, that are building slice templates and profiles, as well as slice models and descriptors. And then after that, standards organisations define how the whole thing should work. So 3GPP is key and defines how 5G network slicing works and how it can be managed. Then ETSI-NFV defines how to orchestrate that based on those 3GPP specifications. ETSI-MEC orchestrates the edge platform and another very important activity is Zero Touch Session Management (ETSI ZSM), addressing how to automate end-to-end slice management.
We are also seeing others fill gaps. MEF is defining end-to-end service level orchestration ZAPIs between domains and carriers and in ONAP there is a network slice use case track in the three last releases, introducing capabilities related to network slicing. Amdocs is leading the slicing modelling work in ONAP, and ongoing work on network slicing inventory support.
Eventually, the challenge is to get all necessary pieces from these different organisations and build a single holistic picture. With this aim in mind, we are participating in and contributing to the above-mentioned organisations, are gaining the required knowledge and expertise, and are building our solution accordingly.
6. That holistic capability will enable a revolutionary change to service providers’ business models
A holistic slice management capability will enable service providers to give enterprises their own slices to manage – delivering that third phase, Network Slicing as a Service.
But beyond that, it will mean a revolution in service providers’ business models. That is because, for the first time, service providers will be able to charge not just based on individual subscribers’ sessions and activity, but on the utilisation and performance of a slice or a service.
That is revolutionary. For the first time, not only can we generate a subscriber or session-based charging report in the mobile network, but a whole slice level report,
We will soon have the capability, as part of 3GPP R17, for the network management and orchestration entity to become a charging trigger function, by which I mean it will be able to report into the charging function information about for example a slice’s capacity, bandwidth, level of latency and performance. And by having all those reports, service providers will be able to charge the enterprise based on, for example, the capacity and performance of that slice as a whole.
That is revolutionary. For the first time, not only can we generate a subscriber or session-based charging report in the mobile network, but a whole slice level report, providing a new monetisation opportunity for service providers, working with enterprises.
7. End-to-end, cross-domain, multi-vendor network slicing orchestration is not about technology, it is about changing our industry.
I have described the technical aspects of slice management. But the important thing to remember is that this is about enabling a revolution in how operators monetise their network assets.
The ability to change the business model, to charge by slice and not per subscriber, to enable B2B and B2B2B models based on Network Slicing as a Service, rests on the ability to manage slices in an automated, zero-touch and closed-loop way, top down and across the network.