SDN – It’s not dead, but do we understand what it was trying to teach us?

SDN lives on, just not in its original form. The initial concept of software defined networks (SDN) asked IT departments to reconsider their entire network architecture, re-writing what many have spent years and dollars building. That was an optimistic ask and organisations were simply not ready to take that leap, but that doesn’t mean it’s intent and ambitions have been ignored. 

What many organisations are doing now is leveraging SDN features and incorporating them into existing infrastructures to deliver on the agility, automation and serviceability promises of the original SDN. New technologies such as SD-WAN are piggy backing onto what SDN started. A flexible, scalable and centrally managed approach that decouples software and hardware to dynamically manage and provision networks. 

SD-WAN, software defined wide area network, took SDN’s concept of dynamic connectivity and created a virtual architecture that can securely connect users and applications by routing the WAN. It forms an overlay across your network to centrally control how, where and what can be connected. With the smarts to understand traffic conditions, it uses the optimal service network based on your location, which could be a combination of broadband, 4G and cable, to send information without any disruption to the user. 

There’s a lot to like about SD-WAN 

• Performance will see a marked improvement. As traffic is distributed, it means you can select how to spread the load, alleviating any bandwidth limitations and pressures.
• The ability to leverage consumer-grade internet and WAN infrastructure is now a viable option, and this will result in savings. 
• Central management and control of branch networks will not only reduce your security risks but simplify processes. It means you can execute firewall deployment, threat detection software, access restrictions and so on at a much faster rate.
• SD-WAN, in most cases, will have security measures built-in but you can also easily integrate a range of additional features to meet the needs of your organisation.

SD-WAN is returning the agility, responsiveness and serviceability that modern networks are demanding. However, like any shift away from your current processes, there are some potential pitfalls to consider.

What are the top challenges?

• Consider your underlying hardware. Some may not support SD-WAN but you should weigh up the cost and efficiency of your current network, and evaluate if hardware replacements will outweigh the benefits.
• SD-WAN is not a simple ‘plug and play’. Design and configuration still needs to occur in the first instance and they require careful planning before it can be ‘plugged’ into your hardware.
• Analysing the services that exist outside of the LAN and determining the best path for these services in leveraging the WAN link connections available