Why SD-WAN is the ‘next big thing’ of the networking world

Software-defined networking (SDN) is at the forefront of today’s networking evolution, enabling organisations to virtualise network infrastructures to provide greater agility and flexibility. As businesses continue to adopt technologies including cloud, big data and analytics, which place increased strain on enterprise networks, SDN in the wide area network (SD-WAN) has emerged as the optimum approach for organisations to take full advantage of the benefits of these technologies.

 

SD-WAN is widely tipped to be the ‘next big thing’ of the networking world, and with good reason. Put simply, the technology adds a software layer over the entire network, giving organisations greater visibility and control than ever before. This, in turn, allows different types of data to be sent through the most efficient and effective pathways at any given time. It does not replace fibre, copper, or 4G links, or even traditional WAN technologies such as MPLS and VPLS. Instead, it abstracts them away, allowing a centrally-managed network layer to be constructed, which looks after both access and WAN technologies.

 

According to a new report from IDC, ‘Worldwide SD-WAN Forecast: 2017-2021’, the global market for SD-WAN technology will see a 69.6% compound annual growth rate, hitting $8.05 billion in five years’ time, as the technology’s ability to address pressing enterprise networking needs leads to significant growth. SD-WAN’s rise is in part due to the fact that demand for bandwidth is growing faster than ever before. Software-as-a-Service (SaaS), once considered a disruptive innovation, is now an everyday part of most industries, and the vast amount of network traffic generated by mobile devices is set to be supplanted by that of the Internet of Things. Added to which, the security threats that networks face – from cyber criminals to simple human error – will continue to grow as these networks become more complex.

 

The fact of the matter is that most network infrastructure and WAN systems were built in the days before cloud. As such, they are simply not equipped to cope with the demand and complexity of today’s digital economy, which is where SD-WAN comes in. 

 

SD-WAN allows businesses to extract far more from their existing network infrastructure. It automatically routes traffic based on application type and priority, reducing latency and improving the reliability of SaaS and other services, even when one segment of the network goes down. It optimises the bandwidth that is available to the organisation, reducing reliance on traditional WAN architecture and moving capacity onto the internet. It can also maintain the security of data at all points in the network, minimising incompatibilities and inconsistencies that may give malicious actors a means of ingress.

 

While SD-WAN may sound like a simple concept, it is a complex network overlay that needs careful execution in order to fulfil expectations and provide optimum performance.

 

10 steps to achieving a smooth SD-WAN transition

 

1.       Analyse the IT estate to get ‘SD-WAN ready’

Businesses must fully understand their IT estate and how it all works together. This includes business applications and associated priorities, traffic patterns and flows, cloud services in use, SaaS models, and how and where to connect to all of these

 

2.       Combining multiple poor access types does not make a good network

Simply bonding together multiple connections does not make for a quality SD-WAN implementation. If they are poorly thought out and executed, they will ultimately disappoint. Businesses need to take the quality and capability of the access lines into consideration to ensure that application performance expectations are met. For instance, a business may require low-latency access for a voice over internet protocol (VoIP) application, while a higher bandwidth access type will be needed for video broadcasting

 

3.       Assess how SD-WAN will integrate into the current infrastructure

SD-WANs do not cover all of the network functionality. A business considering an implementation will need to consider how it can integrate SD-WAN into the wider infrastructure during the design process. This analysis should highlight application and protocol usage to better understand routing and bandwidth

 

4.       Ensure SD-WAN fits into the cloud strategy

Cloud connectivity is a critical issue. Organisations should ensure that SD-WAN will operate in their chosen clouds. Some SD-WAN solutions will only provide a path to public cloud providers using a central hub-style internet breakout, others only through a local internet breakout. Also, these solutions may not be optimised for either latency or performance, or may support only a limited selection of cloud providers. Businesses should carefully consider this, otherwise they may risk not realising the benefits that SD-WAN can deliver

 

5.       Map the connectivity flows of applications

Mapping the connectivity flow is essential to setting up routing policies for deploying SD-WAN. Establishing a detailed design to ensure that available application bandwidth is allocated fairly and based on predetermined policies is also advisable. Businesses should study their application usage and be clear on routing, bandwidth and performance requirements. This will tailor a robust platform that provides users with the best possible application experience by enabling intelligent path control

 

6.       Use SD-WAN migration as an opportunity to update security policies and business best practices

During the design and test phase, it is essential to test application path steering changes against current and future corporate security and compliance policies. SD-WAN provides a platform for organisations to make more use of the internet, but it is not without its risks. Using the internet could expose the business to attack if the correct protection and practices are not put in place. For example, effectively deploying appropriate encryption and containment policies is an imperative step to ensuring corporate data is secure

 

7.       Carefully plan the deployment and consider running a pilot

An SD-WAN is not simply about connecting points. An effectively implemented SD-WAN will be an intrinsic part of a business, requiring careful design and planning that goes above and beyond what is needed for a traditional network. A pilot will help to iron out any ‘pain points’, determining that the network design supports the required application priorities. It will also ensure that the correct network access types are being utilised. This will help to accelerate an effective SD-WAN roll-out across the business

 

8.       Prioritise sites and applications for migration

The sites and applications that will benefit most from early SD-WAN migration should be prioritised. In order to determine these, a business should think about where applications are hosted and identify key locations in the network. This will influence the design of the migration plan

 

9.       Carefully monitor the network during the deployment phase

Verification and validation of the solution is essential to understanding how the network will perform under pressure. It is also important to monitor the ability for remote branch traffic to leverage both public and private connectivity in an active-active connection mode; verify that business-critical traffic is bring steered across the best performing paths across the WAN, while least important traffic can make use of the most cost-effective route

 

10.   Implement efficient network monitoring

Data collected from SD-WAN monitoring systems can be used to provide full visibility of a WAN and application performance. The rich data provided allows a business to fine tune application and network policies to ensure the network aligns with the priorities of the organisation and its needs, both current and future

 

As with the cloud, businesses can expect SD-WAN to become the norm as the connectivity demands of their customers and workforce continue to grow. A well implemented SD-WAN will give businesses insight and control over their applications – as well as robust edge-to-edge security and improved end-user performance – making it far easier for them to manage the digital trends that are transforming businesses worldwide.