Which major block is not included in the ETSI Network Function Virtualization reference framework?

NFVI is one of the three defined core blocks in the ETSI NFV framework, encompassing the physical and virtual compute, storage, and network resources that host VNFs.

MANO is a formally defined block in the ETSI NFV framework responsible for lifecycle management and orchestration of network functions and infrastructure resources.

The ETSI NFV reference architecture consists of exactly three blocks: Network Function Virtualization Infrastructure (NFVI), Management and Orchestration (MANO), and Virtualized Network Functions with Element Management Systems (VNF/EMS). No standalone 'Policy Manager' block is defined in the ETSI NFV framework - policy-related functions are distributed across the MANO layer and individual VNFs rather than isolated in a separate architectural block.

The VNF and Element Management Systems block is the third formally defined component in the ETSI NFV architecture, representing the virtualized network functions and their associated management systems.