Cost-Effective Survivable Virtual Network Embedding in the Presence of Physical Node Failures

Network virtualization offers a promising solution for the rapid deployment of customized services by enabling the creation of multiple Virtual Networks (VNs) on a shared physical infrastructure. While numerous VN embedding schemes have been developed to efficiently allocate substrate resources for VN requests, limited research has addressed the implementation of robust backup mechanisms to ensure resilience against physical network failures. In virtualized environments, the failure of a single physical server can disrupt multiple virtual nodes, leading to significant service outages. To prevent such disruptions, it is essential to preallocate backup physical nodes and reserve link bandwidth to facilitate the migration or remapping of VN requests in the event of any failure. Ensuring the survivability of embedded VNs in a resource-efficient manner is thus imperative. In this work, we introduce a novel approach that utilizes star-based graph decomposition combined with dynamic programming to optimize the mapping of virtual nodes and edges to physical network resources. Simulation results demonstrate that our proposed scheme achieves a higher acceptance ratio and more efficient utilization of physical resources compared to existing backup strategies.