Let's consider Software Defined Networks and Network Function
Virtualization. With software‑defined networks, we find a system
that is actually independent of the cloud.
In fact, it was born in the same time as the cloud.
Software‑defined networks are primarily concerned with separating the
control from the data plane and making sure that there is forwarding of
data from network to network, whereas network function virtualization
is focusing on the abstraction of all network services and devices from
their physicality.
There are three layers of the software defined network,
beginning with the application plane, going into the control
plane, and then, finally, the data plane.
It is the data plane that is concerned with the abstraction of infrastructure.
The original abstraction of infrastructure included routers and switches.
The data plane performs an abstraction that leads to the forwarding
of data, and that forwarding of data makes it so that network
engineers are not really concerned about the physicality of the
infrastructure, so they're moving from an infrastructure‑centric
behavior to a data‑centric behavior.
That's an important testing point.
The transition of infrastructure centric to data centric
occurs with software‑defined networks.
At the control plane, there's actually a controller
card or a controller hardware.
That controller hardware is the thing that interfaces all of
the network connections into a control point.
OpenFlow was the original language that was designed for
software‑defined networks control at the control plane.
Now, you have providers like Juniper,
Cisco, Palo Alto, and others that have the capability of receiving
Infrastructure as Code directly onto their devices so that they can be
managed any way that is central in the control plane.
The control plane connects to the data plane by means of southbound interfaces.
These can include network protocols and traditional network operating
systems that run on the devices. At the application plane, you have a
interconnection between the control plane and the application plane by
means of the northbound interfaces. Northbound interfaces can include
things like HTTP, XML, JSON, it's the programmability capabilities that
would allow you to manage the Infrastructure as Code going all the way down
to the equipment. While software‑defined networks can exist independently
from the cloud.
If you were to integrate a software‑defined network into the cloud,
it would be the management plane of the cloud that connects
directly into the control plane of the SDN.
There is an amalgam of services that are controlled by means of network function
virtualization that could include network interface cards,
firewalls, IDSs, IPSs,
and this is how you would have an integration of the
SDN and the NFV working together.
Next, let's consider the virtualization of the
resource pool that is compute services.