SD WAN: Why It’s Time To Rethink Traditional WAN Infrastructure

WAN Infrastructure
The underlying technology and architecture of the Wide Area Network (WAN) have seen little change over the past ten years. The underlying principle of connecting a remote site to a central site, through either expensive MPLS or leased lines, continues to be used by the vast majority of organizations worldwide.

However, while WAN technology has remained relatively static, everything around it has changed significantly. We now deploy software in the cloud and consume applications as cloud-based services. We leverage cloud communications, IP telephony, and video across all sites. End-users are far more mobile and expect to access rich media content from any device in any location, and we face a far greater threat from cybercriminals.

Are traditional WANs outdated?
It is not a question of whether traditional WAN technology is fit for purpose, but more a question of whether there is a better way. Advances in Software-Defined Networking (SDN) has given rise to the Software-Defined WAN (SD-WAN) and this opens up far more possibilities.

Rather than considering the WAN as something that backhauls everything to head office or a central location, it should be considered as something that connects end-users, regardless of their location, to the services they need. These services may be the Internet, central systems and data, or cloud-based SaaS applications.

The WAN should no longer be thought of as what connects your infrastructure together but as an integral part of your infrastructure. Something you manage as part of your complete network and most definitely a component that you secure.

So, what are the benefits of SD-WAN?
Adopting an SD-WAN architecture such as Cisco SD-WAN (Viptela) or Cisco SD-WAN (Meraki) opens up the opportunity to dynamically align your WAN infrastructure to the needs of each location and each end-user. In doing so you reduce both connectivity costs and management overhead. Here are just some of the benefits delivered by SD-WAN.

According to Gartner, 93% of organizations plan to deploy an SD-WAN over the next two years.

(i) Lower Cost Options

Traditionally each site is supported with a primary link back to a central location and sometimes a secondary link used as a back-up. With this configuration, all traffic regardless of ultimate destination is backhauled over expensive point-to-point connectivity.

Today a significant proportion of WAN traffic is not destined for the central location but to the Internet or cloud-based applications. Therefore, backhauling this traffic through the central location is neither necessary nor the most efficient route. SD-WAN enables you to combine direct connectivity at local sites with cheaper, direct Internet access and dynamically routes traffic based on the required destination, the most efficient route, quality of service, cost, or an application-specific requirement.

This enables you to reduce the bandwidth requirement on expensive services, utilize lower-cost Internet connectivity, or better utilize fall-back circuits.

(ii) Best Performing Options

SD-WAN not only allows intelligent routing based on ultimate destination but also based on performance requirements, balancing traffic across multiple circuit options to deliver the best possible user experience.

The dynamic nature of this intelligent routing means that if an end-user is utilizing one particular route to connect with a web-based application and this link suddenly experiences a degradation in performance, they are automatically switched to the better performing link without interruption of service. The benefit, a far better user experience, and greater service availability.

(iii) Remote Management

With SD-WAN comes the ability to centrally manage your WAN, including local configuration and corporate-wide policies for access, quality of service, and security. This removes the need for on-site expertise and greatly improves service levels that can be delivered to non-central teams.

(iv) Greater Visibility

Because every step of the journey is managed, SD-WAN provides far greater insight into the performance of your WAN and the experience delivered to end-users. Real-time information is provided for failure correlation, cross-customer benchmarking, and application performance. You can model ‘what if’ scenarios and gain assistance in planning application provision, bandwidth increases, and branch expansions.

Cisco takes this even further with their enhanced event-correlation engine, SD-WAN vAnalytics, which helps you cut through noisy event raw data. It uses its contextual analysis to understand when to turn service interruptions into alarms, significantly reducing false positives and unnecessary escalations.

(v) Security By Design

SD-WAN, and in particular the Cisco solutions, enables you to easily manage and more effectively deploy security elements across your WAN. Through cloud management and cloud security services, rolling protection out to remote offices or branches can be as simple as clicking an option.

Such capabilities include firewall, IPS, URL filtering, and continuous DNS monitoring all seamlessly integrating with your holistic security capabilities and providing a single view on the end-to-end network.

The arrival of SD-WAN has most certainly enabled a step-change in the capability, management, and performance of the WAN and must be part of the technology roadmap of any geographically dispersed organization.

How Do You Start
HighPoint is helping organizations to become more agile through digital transformation. What underpins this is helping these organizations to evaluate, design and deploy Secure Software-Defined Infrastructure.

Our expertise is in these forward-looking technologies and our experience is in guiding our clients through their transformation programs and projects to deliver the desired outcomes.

Written by Neil Dearman, Head of Technology, HighPoint