DT-SFC-6G: Digital Twins Assisted Service Function Chains in Softwarized 6G Networks for Emerging V2X

Vehicle-to-X (V2X) with specific user-defined performance metrics emerges as one vital application scenario in sixth generation (6G) networks. According to released reports and whitepapers, 6G networks are designed to have softwarization attributes. Through softwarization, tailored V2X services, constituted by softwarized (resource and function) blocks, can be deployed on top of underlying network appliances. Chaining these softwarized blocks in predefined order is abbreviated as service function chain (SFC). However, existing SFC studies are conducted on the assumption that no performance descending of network appliance exists. Due to inherent shortcomings of softwarization, the softwarized 6G network appliances will bring about performance descending, compared with dedicated hardware. Emerging digital twin (DT) technology paves one way for studying SFC placement and scheduling without worrying about performance descending. By creating a digital replica of softwarized 6G networks, tailored SFCs can be implemented efficiently. This article investigates the SFC placement and scheduling in DT-em-powered softwarized 6G networks for emerging V2X. First, a novel business model and a problem model are presented. Next, one framework design, abbreviated as DT-SFC-6G, is proposed, including all technical details. The DT-SFC-6G design guarantees to provide efficient placement and scheduling solution per SFC request and feedback SFC solution and digital replica's state to softwarized 6G networks in time. Furthermore, experimental work of DT-SFC-6G is conducted. A variety of SFC algorithms, inserted in the DT-SFC-6G design, are evaluated in order to highlight the feasibility and merits of DT-SFC-6G. Finally, three most promising directions of SFC in DT-empowered softwarized 6G networks are selected for discussions.