Introducing a Software-Defined WAN (SD-WAN)
Implementing branch offices for Enterprise organizations can be a challenge regardless of whether there is one branch or hundreds of branches.
One of the many challenges that enterprises face is the selection of technology used to connect headquarters with each of the individual branch offices.Traditionally, the technology selected included leased lines or Multiprotocol Label Switching (MPLS) access links.
The problem is that, while both provide a guaranteed amount of service, they also come with a high price tag.
To bridge the gap between these two disparate technologies, a new WAN service has been developed that couples medium to high service quality along with a relatively low price tag: Software Defined WAN (SD-WAN).
So, what defines SD-WAN software?
To answer this, we first need to briefly cover what this term means in modern networking.The term describes a technology that is a subset of software defined networking (SDN).
At a high level, the goal of SDN is to remove the requirement to configure each individual networking device across the network.
This is handled by splitting up the functionality of these devices.
Traditionally, each of these devices handle three different duties: management, control, and data forwarding:
** The management plane is responsible for the management of the device and the configuration of the device.
** The control plane is responsible for taking the configuration and managing the data forwarding decisions for the device.
** The data forwarding plane is responsible for the forwarding of the data.
With SDN, these duties are split; the device that is deployed has its control plane functionality shifted to a centralized controller, effectively removing most of the complexity from the device and leaving it having to handle only forwarding responsibilities.
For example, if a branch is connected via multiple Internet connections, the SD-WAN device could be configured to use these links simultaneously to take advantage of the qualities of both connections (vWAN).
SD-WAN can expand on this to monitor each of the connections to determine the ones that are currently providing the greatest service quality and then only use those links to forward higher priority traffic.
If you choose to add an MPLS or leased line link, the traffic flowing over these connections can be controlled as well.
For example, traffic going to the central office could be directed to use one of these links while traffic destined for the Internet or directly to a cloud provider could follow a more direct path.
Connections to branch offices will continue to get more complex as time goes on and as new services are offered while, at the same time, organizational budget continue to shrink.
The connection possibilities that SD-WAN offers allows enterprises to have the flexibility to configure their branch connections in whichever way they require depending on the traffic and budgetary needs.
Unlock the Potential of your WAN