By Doug Farndale, Vice President Asia Pacific, Silver Peak

Software-defined wide area network (SD-WAN) technology is the latest advance in a steady evolution that continues to make business communications easier, more agile and less expensive.

SD-WANs are picking up momentum as businesses of all sizes look to evolve their networks to meet the demands of digital transformation, the Internet of Things (IoT), and other trends.

In fact SD-WAN is tipped to have the same impact that cloud had on the IT industry when it first launched.

But how does a business know when it is ready to make this shift? An SD-WAN differs significantly from a traditional network and requires new ways of doing things.

Here are five steps that businesses must take before implementing an SD-WAN:

1. Make sure the infrastructure is ready. For some companies this might mean upgrading hardware, and for others software, but for most it's probably both. For all, it is important to think ‘end to end' to ensure that all the elements across their communications networks are ‘SD-WAN ready' before deployment. They need to make sure their networks, and all their component parts, are completely up-to-date and working at peak efficiency before the project begins.  
2. Do an application audit. To wring maximum benefit from an SD-WAN deployment, businesses need a sound understanding of what applications traverse their network and what communications traffic patterns are like – essentially what digitised information is going where. It's essential to know what dependencies the various applications have, which ones are subject to what types of network issues. Problems include packet loss, where chunks of information fail to reach their destination; jitter, which slows data travelling across the network; and delay.  How much network capacity each data type consumes is another key factor. A business might choose a hybrid WAN, where part of the network allows data to run across broadband, while the rest still uses traditional MPLS (multi-protocol label switching) communications. MPLS is geek-speak for the technology that has driven networks successfully but very expensively for a decade or more. An SD-WAN can handle both Internet and MPLS, allowing a business to move to a full Internet-driven network when its current MPLS contracts terminate. This setup can yield savings as high as 50-60 per cent.  Before moving to an SD-WAN, network managers need to understand which applications must run over MPLS and which ones will run on broadband without a significant drop in performance. An application audit can answer all these questions and help organisations to build an application strategy. Without this, the impact of an SD-WAN will be minimal.  
3. Review the organisational structure. To prepare the way for an effective SD-WAN, a company's IT network, application and compute teams need to work together as a tightly integrated team. Since security, applications and compute infrastructure are highly dependent on the network, a significant amount of collaboration will be required to ensure that business productivity does not suffer.  
4. Rethink IT security. Securing a legacy network is relatively straightforward as there are few ingress/egress points and attack surfaces. Although data traffic patterns change in an SD-WAN, as branch offices have direct Internet access, Security will usually need to protect the same number of end users, which will require no procedural changes. The team will simply need to accommodate higher data volumes passing over the Internet. Hence the SD-WAN may be deployed relatively easily from a security point of view. However, in a software-defined world it is important to have security solutions that will continuously gather network data, analyse it and look for anomalies. In this way security will become pro-active rather than reactive.  
5. Evolve network operations skills. When the network infrastructure is ready and the applications have been studied, a business needs a network operations team capable of supporting it. Managing virtual workloads, network architectures, orchestrating services and analysing data requires significantly different skills compared to managing network routers. If an organisation lacks appropriate internal skills, it should consider using a managed service as a way of bridging the gap. Evolving to an SD-WAN offers a strong ROI for businesses but many of the benefits could be negated if the proper pre-work is not carried out carefully. Be aggressive with an SD-WAN, but remember it is essential to ensure that the organisation is ready.

By Doug Farndale, Vice President Asia Pacific, Silver Peak