AttachSFC: Optimizing SFC Initialization Process through Request Properties

Network Function Virtualization (NFV) technology enables the decoupling of Network Functions (NFs) from hard-ware by initializing them into virtual machines or containers, which can provide more flexible and customized services to users. However, in current NFV networks, the NFV Orchestrator (NFVO) needs to initialize an Service Function Chain (SFC) containing one or more Virtual Network Functions (VNFs) for each request. This is not appropriate in most cases. On the one hand, the initialization of VNFs also needs to be delayed, which can affect the quality of service to some extent. On the other hand, most of the requests in the network are low-resource and short-occupancy, and such SFCs will be born and died frequently in the network, which will affect the stability of the network. Unfortunately, optimising VNF initialization is a necessary but easily neglected issue. In this paper, we design AD- NFVO for Internet Service Providers (ISPs) to simplify the initialization process of SFCs and increase the overall reward of the network. Firstly, we classify user requests in terms of time and size, respectively, and propose AttachSFC, an adaptive SFC attachment strategy to simplify the initialization process of SFCs. Secondly, we apply AttachSFC to NFVO, and since AttachSFC and SFCs deployment is interdependent, we use the Advantage Actor Critic (A2C) strategy to optimize them to increase the overall reward of ISPs. Finally, we experimentally demonstrate the effectiveness and potential of the AD-NFVO.