According to European Telecommunications Standards Institute Industry Specification Group (ETSI ISG NFV), the MANO function is responsible for deploying and connecting hosted elements or virtual network functions.
NFV MANO is broken up into three functional blocks:
NFVI block is the NFV Infrastructure that includes physical (server, storage etc.), virtual resources (VM’s) and Hypervisor in an NFV environment
There are two blocks outside of MANO, i.e. Element Management System (EMS) and OSS/BSS. They are not directly part of the MANO but they do exchange information with it.
Here is a short description of each of these blocks.