SDN stands for Software-Defined Networking, and unless you are an IT wiz, you are probably a bit confused about what it is exactly and what it does and why you would need it. It is a reasonably new networking architecture, IT departments and wireless expense management companies all over the place are still trying to get a handle on it.

In a nutshell, SDN is a way to configure your network and control it much more centrally without the need for a ton of hardware and lots of individualized sectors of programming within one network. To better understand what SDN is you should know the old method of networking that SDN is rapidly replacing.

How the Internet Used to Work

The way that data is sent over the internet is through something called IP protocol. IP Protocol essentially segments data that is sent from one point to another so that the system can make sense of it and send it to where it needs to go based on their IP addresses.

This is something of an antiquated system however as more substantial amounts of data (as we are currently seeing in the IoT and cloud computing boom) become increasingly hard to manage using the basic structures of IP Protocol.

So enterprises and large data centers are looking for a better way to manage their data and SDN has emerged as the next frontier for system networking and data routing. So what is it?

How SDN Works

A software-defined network essentially makes complicated network structures much more manageable by allowing the user to directly program all of the functions of a large network from a single point. Let’s say for example that it is 2005 and you want to install a firewall between one of your routers and your central system hardware. To do this, you would have to go in and find the specific point that you want to secure and program it locally at that point.

Let’s flash forward to 2019, and you still want to put up a firewall between a router and your main system hardware. With SDN you don’t have to go in, find the point and install it right there. You can program the firewall from a centralized location.

To take it one step further, users can even control an entire complicated networking through special application programming that essentially manages the whole system itself and feeding the data to the user for ultimate supervision.

One of the ways it allows for this functionality is by virtualizing the network. In SDN’s infancy, it’s use case was simply to eliminate the need for specialized hardware and virtualize the network by separating the control plain that is in place to control the physical network from the data plain that manages how network traffic flows.

To put it in as simple terms as possible an SDN works by allowing the user to control a vast network centrally as opposed to having to program locally.

How is this Advantageous?

The most immediate advantage of running an SDN is that the network architect can much easier build an extensive system. By being able to control various individual networks centrally, the user can build networks that are much larger and much more complex.

SDN not only makes spinning up your network easier but it makes scaling down easy too. Eliminating specific networks and streamlining the whole can be done in half the time that it would take for traditional network architecture.

Another case for SDN implementation is specific application installation. Specialized business applications such as Voice Over Internet Protocol can be easily installed on a dedicated portion of their large-scale network using the SDN architecture. This allows for supreme customization of a network through which you can install certain applications for one area of your network and leave another area dedicated to something else.

Security is another advantage of SDN. Specific security measures can be taken on specific network locations very easily with SDN. The SDN user can also microsegment their network connections and create something called a public facing network to protect their secured network that is managing all sensitive data. The public facing network acts kind of like a decoy so that hackers access it instead of the secured network. The public facing network will restrict a hacker to the server sector of the network where little to no damage can be done.

In the end, the main advantage of SDN is economical. Say for example that you do want to start using a VoIP system instead of a traditional phone service. This technology alone is emerging quickly because it saves businesses a lot of money. Now couple that with an SDN where a VoIP can be easily and quickly installed without wasting a lot of time and money and you have just made your system much more economical.

The SDN Trend

The original uses for SDN were somewhat limited but SDN has multiplied over the last few years, and it is an upward trending network architecture. Today users can program applications that run entire systems autonomously and locate problems within the system much quicker than before. Which helps the network inventory management within the network. 

The automation of network configuration is another important use for SDN that is advancing as we speak. SDN allows the network to be configured on the fly as needed essentially.

There is huge growth room for SDN and understanding it is essential because all indications suggest that SDN is the way networks will be configured from here on out.