An extensible Autoscaling Engine (AE) for Software-based Network Functions
With the rapid migration towards Software-based Networks, Telco Operators are modifying their traditional network infrastructures in order to reduce the complexity in managing Network Services (NS). Being able to cope with on-demand traffic increase is one of the key principles taken from the Cloud Computing domain and extended to the Telco one by the ETSI Network Function Virtualization (NFV) initiative. However, due to the novelty of this paradigm in the Telco domain, the landscape of fully-interoperable frameworks is rather limited and even more complex is their extensibility for supporting new functionalities. None of the existing solutions nowadays provide mechanisms for dynamically adapt the NS topology based on their Runtime Key Performance Indicators (KPIs), supporting the requirements requested by the ETSI NFV specification. Therefore, this article presents an Autoscaling Engine (AE) capable of dynamically adapting a NS based on policies provided by the Operator and integrated in the ETSI NFV information model. Its design has been realized considering the NFV requirements, and has been integrated in the ETSI NFV Architecture as additional functional element. Its implementation is part of an existing NFV-compliant framework, Open Baton, and made available to the community as open source. An evaluation of the implemented concept shows that the proposed solution increases the reliability, stability and resource efficiency of NSs.