Virtual Network Reconfiguration with Load Balancing and Migration Cost Considerations

Efficient allocation of resources is an essential yet challenging problem in a virtual network environment, especially in an online setting whereby virtual network requests may arrive, depart, or be modified in real time. Virtual network reconfiguration may help to improve network performance by remapping a subset of virtual nodes or links to better align the allocation of resources to current network conditions. In this paper, we develop a virtual network reconfiguration scheme that aims to balance the load on the substrate network by dynamically reconfiguring the embedding of both virtual nodes and links. Our solution consists of decomposing the problem into two subproblems: i) virtual node selection, for which we present a linear programming-based fully polynomial time approximation scheme to select the virtual nodes to be migrated, and ii) virtual node remapping, for which we make use of random walk on a Markov chain to select new substrate nodes for the migrated virtual nodes.