A joint network and server load balancing algorithm for chaining virtualized network functions
Chaining virtualized network functions (VNF) is an effective practice to deploy network services in network operator's data centers. Two common concerns arise in such a deployment are network load balancing and server load balancing. In this study, motivated by the argument that such two concerns should be jointly addressed for efficiently chaining VNFs in a data center environment, we propose a 2-phase algorithm, Nearest First and Local-Global Transformation (NF-LGT), which concurrently supports network and service load balancing. The algorithm firstly constructs service chains by a greedy strategy which both considers network latency and server latency. Then a searching technique is applied to improve the solutions. We have implemented the algorithm using Software-defined networking (SDN)/OpenFlow concept. The experimental results indicate that, compared with a sequential approach, NF-LGT improves the system bandwidth utilization up to 45%.