Towards Secure and Optimized Cross-Slice Communication Establishment

Network slicing has been at the forefront of 5G network research, with various slicing orchestration architectures seeking to reap the benefits of slicing for the enhanced performance and reliability of 5G (and beyond) network services. In this context, cross-slice communication (CSC) has drawn significant attention, since CSC can foster interactions among services deployed in co-located slices, lowering the barrier for the consumption of services.To capitalize the benefits of CSC (e.g., reduced latency and cost), CSC should be established with the highest degree of co-location and also in a secure and policy-compliant manner. To this end, we present an orchestration framework that fulfills all main technical requirements for CSC instantiation. In this respect, we elaborate on the CSC instantiation workflows and shed light into the cross-layer interactions that span our proposed CSC orchestrator, the Network Function Virtualization Orchestrator (NFVO) and the Virtualized Infrastructure Manager (VIM). Our experimental results indicate that our proposed CSC orchestration framework introduces a negligible performance overhead and also incurs a minimal latency inflation compared to a direct form of inter-slice communication without any provision for security and resource isolation.