Tomorrow’s SD-WAN – Driven by Application Experience

There’s an old retail adage that the customer is king. Well, extending that ideology into today’s digital business, we might say the user is king. Whether it’s customers, partners, or employees, they’ve all come to expect an application experience that is always-on. They don’t care if the source of the problem is the application or the network: things should just work.

Today’s modern enterprise is in the midst of a network and cloud transformation. Networks are supporting more business-critical applications than ever before and at the same time these applications are increasingly migrating toward SaaS and multi-cloud environments. To build the right enterprise network for tomorrow, enterprises are embracing SD-WAN. As they do so, they may want to consider an SD-WAN that is driven by application experience. Here’s why:

A cloudy world, it is

There was a time not so long ago where one cloud vendor was the predominant choice. While this may still be somewhat true, customers are embracing multi-cloud in a big way. Various research suggests that over 50% of enterprises are already executing a multi-cloud strategy. Some enterprises (retail, healthcare, automotive for example) have done this due to competitive reasons while others are pursuing this approach as a best practice to ensure resiliency into their network design.

Multi-cloud support (AWS, Azure, Google Cloud Platform, and more) should be an imperative for any SD-WAN. While virtual deployment in such environments is a first step, enterprises should also consider automation. Can IT teams apply zero-touch to bring up the SD-WAN instance without any swivel chair operations? Is the SD-WAN solution automatically configuring security and connections as cloud workloads change? Failover time would also be worth examining with these cloud connections. Since many mission-critical applications are now being run on IaaS, the last thing an enterprise needs is for a down link to disrupt users for minutes or worse.

Why should SaaS get a pass?

When it comes to early usage of SaaS, we seem to have conditioned users to accept best-effort performance. Like with a mobile phone, if the connection drops or breaks up, we call back. Just like the mature mobile network, call drops, audio quality and overall experience do matter to business, a lot! In most cases, SD-WAN connections to SaaS are not resilient, since there is an SD-WAN appliance at the branch but not one that “front ends” the SaaS cloud. As such, if an enterprise wants multiple network connections for resiliency and always-on SaaS, this would not be possible.

Automated provisioning, QoS, and visibility and monitoring – these might also be required. In examining SaaS reliability with SD-WAN, how these areas are handled would be valuable considerations. Also, is there an alternative to using the public internet for better performance such as an enterprise-grade, private network?

Applications lead, networks follow

There is a theory propagated by some in the industry that throwing bandwidth at a performance issue will solve the problem. This may solve some problems, but many enterprises prefer to take a more pragmatic approach of slightly overprovisioning to accommodate growth but not necessarily doubling bandwidth to avoid optimizing for applications.

For those who want to address application performance, understanding how their SD-WAN identifies, classifies, and optimizes applications – especially those from the cloud – could be quite valuable. If the SD-WAN has visibility into Hangouts Chat as part of G Suite or Teams as part of Office 365, QoS and packet replication can be applied so that those sessions stay on even in the case of link issues. Obviously, this level of reliability and performance can go a long way if the meeting happens to be with a valued business customer or partner.

Lastly, let’s not forget about the virtual applications that still reside in data centers. Along with those running in public clouds, on-prem applications like EHR (Electronic Health Records), CAD/CAM, and virtual desktops also require optimization. A VoIP session within a virtual desktop should take precedence over a file sync; a patient record download should be prioritized over access to the corporate intranet. IT teams should evaluate how an SD-WAN manages and prioritizes traffic from these and their sub-applications along with counterparts from SaaS, IaaS, and PaaS.

There is much more to take into account as enterprises evaluate SD-WAN, but the focus on application experience and these foundational areas are worthwhile considerations. The symbiosis between network, cloud, and applications is critical for building a network that addresses tomorrow’s requirements.

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Author's Bio

Chalan Aras

Vice President, SD-WAN and Intelligent Traffic Management, Citrix