SLA Decomposition for Sustainable End-to-End Multi-Domain Multi-Technology Network Slicing

The sixth generation (6G) networks will integrate many autonomous networks operating in different administrative domains and wireless technologies. Hence, service provisioning involves negotiation between multiple stakeholders (e.g., users, operators, manufacturers) to reach a service level agreement (SLA). To ensure its sustainability under dynamic network conditions, the SLA must be dynamically decomposed into portions each domain can support. Failure to do so will result in SLA violations and user dissatisfaction. In addition, management and orchestration schemes for SLA decomposition are needed to facilitate mapping service requirements to the most suitable domains, providers, and technologies, and perform SLA lifetime monitoring. However, SLA decomposition is challenging with management decisions at different levels and interdependent performance implications. Despite the relevance of this topic, it remains unexplored. This article aims to fill this gap and presents an SLA decomposition management and orchestration architecture for multi-domain, multi-technology networks that supports centralized, semi-distributed, and fully distributed implementation. The proposed architecture is well aligned with the guidelines provided by standardization bodies. We evaluate its performance for typical 6G use cases and show that our approach achieves up to six times higher reward with half the cost of existing schemes. Finally, remaining challenges and promising future research directions are outlined.