Scalable and coordinated allocation of service function chains

Network Functions Virtualization is an emerging initiative where standard IT virtualization evolves to consolidate network functions onto high volume servers, switches and storage that can be located anywhere in the network. In NFV, network services are built by chaining a set of Virtual Network Functions (VNFs) that must be allocated on top of the physical network infrastructure (commodity hardware). This challenge is commonly known as the NFV resource allocation problem, that is divided in two problem stages: 1) service chain composition and 2) service chain embedding. Up to now, existing approaches do not scale with regard to problem size. In this paper, we address this problem and propose CoordVNF, a heuristic method to coordinate the composition of VNF chains and their embedding into the substrate network. Evaluation results show that the heuristic is able to quickly solve the allocation problem even in substrate network topologies with hundreds of nodes.