more recent concept that stems from the advent of
network controllers, which split role and functionality
from one another. This is often referred to as separating
the control plane from the data plane. At a high level, the
control plane is where all the instructions on a device live
(for example, the routing protocols that exchange routing
updates). The data plane is where all the user or data
traffic flows (for example, the traffic between users on a
network). Having a controller that sits on top of the rest
of the devices makes it possible to operate the network as
a whole from a centralized management point—much
like operating an automobile from the driver’s seat rather
than trying to manage the automobile from all the pieces
and components of which it is composed. To put this in
more familiar terms, think of the command-line
interface (CLI). The CLI was not designed to make
massive-scale configuration changes to multiple devices
at the same time. Traditional methods of managing and
maintaining the network aren’t sufficient to keep up with
the pace and demands of the networks of today.
Operations staff need to be able to move faster and
simplify all the operations and configurations that have
traditionally gone into networking. Software-defined
networking (SDN) and controller capabilities are
becoming areas of focus in the industry, and they are
evolving to a point where they can address the challenges
faced by IT operations teams. Controllers offer the ability
to manage a network as a system, which means the policy
management can be automated and abstracted. They
provide the capability of supporting dynamic policy
changes rather than requiring manual policy changes
and device-by-device configurations when something
requires a change within the environment.
It is important from a career and skills perspective to
adapt to the changes within the industry. Keeping on top
of new skillsets is critical to maintaining relevance in the
industry or job market. Becoming Cisco certified helps
with this for multiple reasons, including the following: