Online Load Balancing for Network Functions Virtualization

Network Functions Virtualization (NFV) aims to support service providers to deploy various services in a more agile and cost-effective way. However, the softwarization and cloudification of network functions can result in severe congestion and low network performance. In this paper, we propose a solution to address this issue. We analyze and solve the online load balancing problem using multipath routing in NFV to optimize network performance in response to the dynamic changes of user demands. In particular, we first formulate the optimization problem of load balancing as a mixed integer linear program for achieving the optimal solution. We then develop the ORBIT algorithm that solves the online load balancing problem. The performance guarantee of ORBIT is analytically proved in comparison with the optimal offline solution. The experiment results on real-world datasets show that ORBIT performs very well for distributing traffic of each service demand across multipaths without knowledge of future demands, especially under high-load conditions

Dynamic traffic steering of multi-tenant virtualized network functions in SDN enabled data centers

Network Functions Visualization (NFV) builds upon virtualization technology and allows the decoupling of network services from dedicated and complex hardware-based appliances. This decoupling allows network providers to install these functions in commercial off-the-shelf hardware reducing the overall capital and operational expenses. In order to provide complete and high quality services to the end users, a series of these functions may need to be traversed creating a service chain model. In this paper, we study the problem of allocating a dynamic service chain, where a random number of users are associated with each service chain, in a data center network. The allocation consists of the placement of VNFs in appropriate servers and the interconnection between these servers. This interconnection is facilitated by an SDN controller, which proves to be complementary with the NFV paradigm. Towards these aims, we propose two algorithms for the placement of the VNFs, while the SDN controller periodically recalculates the routing paths to adjust to the dynamic traffic conditions