# On the Rollout of Network Slicing in Carrier Networks: A Technology Radar
## 9 Conclusions  
As 5G standards get completed and commercial products mature, operators shall demonstrate their ability to efficiently combine available technology solutions to deliver network slices for different customers, with a number of these slices being short-lived and provisioned on demand. Network slicing may allow network operators not only to achieve relevant CAPEX and OPEX reductions in their managed network infrastructure, but also to significantly enrich their portfolio with innovative service offerings, which is a key differentiator in the highly competitive environment the provision of network services has become today. Network slicing is an E2E solution that has an impact on all subsystems, including the different technology domains (including RAN, CN and TN) and the operational systems (the OSS). The main problem is that the degree of maturity of slicing support is quite different in these subsystems. Indeed, while the CN is the technology domain that currently supports the most advanced slicing capabilities, the TN is still in and early phase, with RAN domain sitting in between. In the case of the OSS, in charge of the management of these three technology domains and of the orchestration activities across them, we can find different paces of technology evolution. According to the above rationale, it is clear that it may take several years for operators to prepare their systems to fully harness the power of network slicing, and become able to support NSaaS. Awaiting this moment to start commercializing and monetizing network slicing is not an option, either for operators (who cannot offset the costs associated with the introduction of slicing capabilities into their assets) or for customers (which may not need the full set of capabilities for their use cases from the very beginning). In this context, what the industry demands is a phased-based rollout of slicing, starting with early-stage solutions and outlining a vision of what is desired in the longer run to guide progress and focus. In this article, we have presented a radar with the mission to help industry in defining this rollout. This radar captures a complete landscape of network slicing solutions, linking these solutions to different timelines based on their technical viability and market demands. In addition to this timing, the radar has also outlined the dimensions that have an impact on the usability (how and where) of these solutions, across all operator managed domains. In the RAN domain, network slicing solutions have been discussed based on functional aspects (e.g., disaggregation and O-RAN integration), radio resource allocation and penetration in the operator's cell footprint. In the CN domain, discussions have been around the fulfilment of isolation and customer requirements of network slice customers, resulting in the use and combination of different 5 GC functions, with different profiles. In the TN domain, solutions have been articulated around the technology capabilities available in the underlay WAN, complemented with the automation and programmability capabilities brought by SDN technology. Finally, in the OSS domain, aspects related to network slice OAM and capability exposure have been addressed, with a focus on provisioning and assurance activities. The network slicing solutions captured in the radar have been analyzed based on their timeline, together with the above dimensions in Sections 4-8. In order to provide the reader with a common reference system to interpret the content of this radar, we started this work by providing the technical background of network slicing (Section 2) and its impact on individual technology domains (Section 3). We are confident that the radar presented and discussed in this article will be a valuable reference for operators to outline their network slicing rollout plan within their service footprint.