Another definition of software defined networking is software defined networking via API ease or application
programming interfaces.
In this vision rather than being tied to configuring a network device via a command line interface which
is very restrictive.
Why didn't we have richer programmatic interfaces on networking devices.
An example would be let's use a RESTful API rather than a basic SEO lie.
Other protocols like Ovi SDP a net conf could be used to programmatically change the configuration of
a networking device.
Now you may be thinking well I'll just use simple network management protocol or S&P.
S&P has some restrictions and doesn't work particularly well when you want to change the configuration
of a device.
Another definition would be using ASX and I've put this as a separate vision of SDM and there will be
a separate course on Cisco ECI using a protocol called a plex.
Cisco purchased a startup called in semi and they have developed a vision of SD in using hardware or
ASX.
So the Cisco solution is very reliant on an async implementation and ties in with their nexus product
line.
Other terms you may come across include cloud automation using open stack.
One of the visions with open stack is that we should be able to manage all our networking devices servers
and storage from a single management console.
We'll talk more about Open stack in a separate course.
What about in a V or network function virtualization.
I'd recommend that you visit the OPI in a V Web site for more details about in a V but to give you a
very quick overview of NFP is why do you run specific operating systems on specific hardware to provide
a function as an example.
Why do you have a hardware firewall that just provides that function.
In the past you had servers that had specific functions installed on specific hardware.
As an example you may have had an Exchange server or a database server or a file server every server
was running on dedicated hardware.
Then a few years ago servers got virtualize.
So you no longer run.
For instance some server platforms on hardware you run them within virtual machines and typically you
would run many virtual machines on a single hardware device.
And there are many advantages to the virtualization of servers in the same way.
Why don't we virtualize networking devices.
So as an example we might virtualize a Cisco router using the CSR or an HP router using a VCR or a switch
using obvious or open v switch.
Many of us have encountered virtual switching in a VM way environment VM Where have virtual switches
running in their hyper visors.
So taking this a step further why don't we virtualize networking devices rather than having a dedicated
rudder or a dedicated firewall.
Why didn't we just run a VM with that function so we could virtualize a firewall or virtualize a router
that we could take it a step further.
So as an example rather than running a Windows operating system just to give me a specific application
like a web server why don't we virtualize the operating system as well and run multiple applications
separated from each other as if they're in different VMs or containers is a term that's often used today
and separate the applications from each other but have multiple applications running on a single server
in the same way why didn't we virtualize a function such as VR or P or a firewall function rather than
running a full blown operating system per function.
Why don't we run one operating system and just instantiate network functions and many of them on a single
operating system.
We'll talk more about in a V in a separate course.
For now I'm going to introduce open SD and add a bit of open flow.
Have a look at more detail courses available on genius 3 I will hopefully be discussing the details
of all of these in upcoming courses.