One of the first software-defined networking (SDN) languages called Openflow was created about ten years ago and was demonstrated at an Interop tradeshow from some Opengear equipment I donated. I was at a trade show and slowly but surely, people began to congregate around our table, realizing what I had recognized as a game-changing idea: An independent management plane. With so much traffic on a typical production network, it’s not feasible to use that same network to make configuration changes, software updates or do any of the other fine-tuning to devices. Ideally, those changes should be made through the device’s serial port - independent from the network itself.
Fast forward to 2021, and we are now essentially doing the same thing, only now we call it a software-defined wide-area network (SD-WAN). SD-WAN vendors are replacing traditional branch routers with appliances that automatically determine the most efficient network paths and shift traffic to optimize bandwidth. These devices are centrally managed, with routing that can be updated in real-time in response to changing network requirements. The technology that comprises SD-WANs has been around for a long time. What is new is an SD-WAN’s ability to dynamically share network bandwidth across connections. An SD-WAN solution today can utilize multiple types of connections, from LTE to broadband to multiprotocol label switching (MPLS) links. Services that require high quality, such as video or voice, or high security, with sensitive information, can still be routed over remaining MPLS lines, although many enterprises are freeing themselves of MPLS entirely. Because of this flexibility, SD-WANs can dramatically lessen the cost and minimize the complexity of traditional WANs.
In the past, enterprises had to have complicated infrastructure at each branch office, with routers, firewalls, WAN path controllers, WAN optimizers, potentially expensive MPLS circuits, and more. Maintaining an MPLS-based WAN is expensive. In most cases it’s also outmoded since a majority of traffic is already headed for a public Internet gateway. The business shift to SD-WANs is coming about quickly because they not only dramatically lower costs, they help businesses become more agile by enhancing business productivity. However, traditional WANs weren’t architected for a dynamic, internet-based environment. Having to backhaul traffic from the branch to headquarters to the internet and back again is inefficient, costly, and prone to disruption. These days, users find that their business apps run faster on their home network or on their mobile devices than on a traditional WAN.
In traditional branch networking, often routers go for months without needing any intervention like configuration changes or firmware updates. But SD-WAN routers are more sophisticated and run a large software stack. Firmware updates are common which means that there are many more opportunities for things to go wrong. And while Cloud-Based Provisioning makes provisioning and configuration of an SD-WAN router easier, ultimately it is still In-Band management, with all access to your network dependent on the same router. Without Out-of-Band (OOB) management, network events become serious disruptions.
While the first SD-WAN evolution stage was focused on solving the issues of availability and bandwidth, SD-WAN 2.0 not only provides a dynamic and flexible service but also includes the components needed to be used for applications like the hybrid cloud. With SD-WAN 2.0, critical applications needed for customer interaction, commerce, and employee productivity can be sent over a traditional connection. Non-critical traffic, like guest Wi-Fi and video, can be routed over a much less expensive internet connection with requisite levels of security and guaranteed performance. Application-aware routing lets you create policies to determine which applications will travel over which transport options, with the flexibility to automatically shift traffic as load and conditions change. SD-WAN 2.0 also provides a dynamic private network service while also matching the requirements and budget of the end-user. SD-WAN 2.0 allows companies to increase bandwidth while lowering network costs and increasing flexibility and choice. However, it also introduces points of failure. Without Out-of-Band management (OOB), network events can become serious disruptions.
Where the efficiency, innovation and financial realms really come together on this is with smart, independent, zero-touch solutions. Enterprises can avoid truck rolls, proactively meet service-level and reduce costs. An independent management plane, allows engineers to do more with less while also potentially saving their companies millions of dollars in both startup and maintenance costs. It’s an inexpensive safety net for your network that provides real value from a proactive management standpoint.
The idea of SD-WAN and the independent management plane started in data centers, but as the Internet of Things (IoT) and edge computing devices have become the norm, network resilience practices have begun to follow suit, extending from the network core to the edge and back. Of course, as the network expands, so does the variety of devices that can be independently managed. With SD-WAN 2.0, an operator can use a portal to gain access and monitor factors like vibration, temperature, smoke and humidity that could be potentially harmful to remotely installed environmental sensors that might literally be buried underground.
As networks become more powerful and widespread, the devices that power them have become more advanced - and more prone to issues that require constant management and maintenance, that’s where Smart Out-of-Band management comes into play. Deploying it with SD-WAN 2.0 eliminates points of failure and gives you secure access to all of your network infrastructure - router switches, firewalls, proactive monitoring, alerts, power management and more - as part of an efficient, cost-effective platform that will allow network teams to do much more - with much less.
