MANOaaS: A Multi-Tenant NFV MANO for 5G Network Slices

The dramatic densification of connected mobile devices and the expected use cases from the vertical industry demand an innovative network design that meets upcoming stringent requirements. The adoption and harmonized integration of novel concepts, such as network functions virtualization and network programmability, enables the system to master the high expectation -- from the fifth generation communication network in support of flexibility -- to provide tailored and mutually isolated network slices, high performance, agility, and automation. This effectively involves a number of technical challenges for managing and orchestrating physical and virtualized slice resources by means of an advanced management and orchestration (MANO) system. This article sheds light on potential benefits and implementation aspects when the MANO framework is abstracted into customized and distributed MANO instances, thereby empowering the MANO-as-a-service (MANOaaS) paradigm. In particular, such distributed instances are provided to different network tenants for a greater level of control on requested network slice(s). The notion of management level agreements in the context of MANOaaS is introduced as well as differentiated per tenant while being embedded into the proposed architecture. We also position the proposed MANOaaS concept and associated extensions to the MANO reference architecture from the viewpoint of standardization bodies and ongoing open source projects.