vNFChain: A VM-Dedicated Fast Service Chaining Framework for Micro-VNFs

Network Functions Virtualization (NFV) has been expected to flexibly compose Virtual Network Functions (VNFs) by virtualizing existing network appliances and logically chaining them. Currently used VNFs are realized as VM-based appliances and shared by multiple users (VMs). However, the notion of NFV can be extended to reinforce network functionality of user VMs by introducing VM-dedicated VNFs. In this paper, we propose micro-VNFs (μVNFs) and a VM-dedicated service chaining framework (vNFChain). Micro-VNFs are VM-dedicated lightweight VNFs (application firewalls, monitoring, and logging), while typical VNFs (routers, firewalls, and load balancers) are centralized and shared. The vNFChain framework creates local service chains of uVNFs for each VM and transparently attaches a chain to the target VM. In practice, our framework supposes process-based uVNFs within a container and can efficiently chain these uVNFs in the context of DPDK/vhost-user mechanisms. We focus on architecture and implementation of the proposed framework in this paper. Evaluation results on commodity PCs showed that our approach achieved about 7.3 times (1 μVNF) and 160 times (6 μVNFs) throughputs with 64-byte packets compared to that of a VM-based service chaining using DPDK/vhost-user. In addition, latency was reduced 88 % with 6 μVNFs.