Enabling Elasticity Control Functions for Cloud-Network Slice-Defined Domains.

The NECOS (Novel Enablers for Cloud Slicing) platform controls the entire lifecycle of end-to-end cloud-network slice instances, so that new services and applications can run in a broader perspective for quality-guaranteed and highly isolated multi-tenancy. Elasticity plays a vital role in ensuring the efficiency of the NECOS platform. According the state of the art, mainstream reactive elasticity solutions are not suitable for dealing with cloud-network slicing-defined systems by the fact that they cannot trigger time-burdensome vertical elasticity on deriving resource-depleting conditions. This gap can be filled by introducing in the elaSticity cLOud-neTwork Slices (SLOTS) solution, which participates in the NECOS platform in the form of new building blocks that interwork with others to add new patterns of cloud- and networking-type resources under resource-depleting conditions. The unique contributions made by SLOTS are as follow, and go beyond the state–of-the-art by: (i) fully supporting cloud-network slice-defined systems; (ii) offering a hybrid elasticity approach; (iii) provide a sophisticated mechanism to enable a slice solidarity approach, and (iv) providing a real lab-premised large-scale testbed for a SLOTS prototyping assessment. Analysis on the evaluation results suggest that SLOTS performs well by accomplishing a higher number of elasticity events under resource-critical conditions, while slightly adding computing overhead, when compared with a widely-used stochastic-based representing solution.