Cloud Infrastructure terminologies

Hypervisor

A hypervisor is a software, firmware, or hardware that gives the impression to the guest Operating systems that they are operating directly on the physical hardware of the host.
It allows multiple guests OSs to share its hardware on a single host.
Manages requests by VMs to access and abstract the physical hardware resources of the host, and allows the VMs to behave as if they were independent machines.
Uses Virtual Machine Manager (VMM) instance to create a one-to-one association with each VM being managed, allowing the hypervisor to securely manage the VM.

There are two types of hypervisors:

• Type 1 hypervisor: hypervisors run directly on the system hardware — A “bare metal” embedded hypervisor,
• Type 2 hypervisor: hypervisors run on a host operating system that provides virtualization services, such as I/O device support and memory management

Data Center Design Standards

Tier 1: Basic data center site infrastructure
Tier 2: Redundant site infrastructure capacity components
Tier 3: Concurrently maintainable site infrastructure
Tier 4: Fault-tolerant site infrastructure