3 Aggregation: If the resource is too small, it
is possible to construct a large virtual
resource that behaves like a large resource.
This is the case with storage, where a large
number of inexpensive unreliable disks can
be used to make up large reliable storage.
4 Dynamics: Often resource requirements
change fast due to user mobility, and a way
to reallocate the resource quickly is
required. This is easier with virtual
resources than with physical resources.
5 Ease of management: Last but probably the
most important reason for virtualization is
the ease of management. Virtual devices
are easier to manage because they are software-
based and expose a uniform interface
through standard abstractions.