Priority-Based Bandwidth Management in Virtualized Software-Defined Networks

In Industrial Internet of Things (IoT) applications, when the network size increases and different types of flows share the bandwidth, the demand for flexible and efficient management of the communication network is compelling. In these scenarios, under varying workload and flow priorities, the combined use of Software-Defined Networking (SDN) and Network Virtualization (NV) is a promising solution, as such techniques allow to reduce the network management complexity. This work presents the PrioSDN Resource Manager (PrioSDN_RM), a resource management mechanism based on admission control for virtualized SDN-based networks. The proposed combination imposes bounds on the resource utilization for the virtual slices, which therefore share the network links, while maintaining isolation from each other. The presented approach exploits a priority-based runtime bandwidth distribution mechanism to dynamically react to load changes (e.g., due to alarms). The paper describes the design of the approach and provides experimental results obtained on a real testbed

Polynomial space hardness without disjunction property

Horčík and Terui [8] show that, if a substructural logic enjoys the disjunction property, then its tautology problem is PSPACE-hard. We prove that all substructural logics in the interval between intuitionistic logic and generalized Hájek basic logic have a PSPACE-hard tautology problem, which implies that uncountably many substructural logics lacking the disjunction property have a PSPACE-hard tautology problem