The Case for SD-WAN: A Primer


SD-WAN is mainstream, and it's here to stay. No longer an emerging technology, it’s is a crucial component of any long-term WAN networking strategy in today's cloud-centric world. SD-WAN simplifies network design and deployment and increases IT efficiency and agility. But as with any paradigm shift, there's a lot you need to know to hit the ground running, so consider this article a short primer on key points everyone should become familiar with as they investigate software-defined networking.

We're not the first to declare SD-WAN mainstream. Late last year Gartner made similar statements in its paper, Technology Insight for SD-WAN.

“SD-WAN is a mainstream technology that offers several benefits compared to traditional, router- based WANs. I&O leaders responsible for planning, sourcing and managing WANs can reduce costs and improve agility and uptime by using SD-WAN products.”

Gartner | Technology Insight for SD-WAN

We believe, this report is a useful resource for understanding the current state of SD-WAN, its use cases, and how it addresses the shortcomings of legacy routing. You can download the full Gartner paper to read for yourself. 

Here’s the Riverbed perspective on SD-WAN.

SD-WAN is an elegant antidote to complexity

Network complexity is increasing due to many factors, including the use of hybrid WANs and a growing dependence on cloud-based applications. Traditional methods of managing WANs cannot scale to meet this added complexity. Who, for example, has time to write hundreds of error-prone command lines.

With an SD-WAN solution like Riverbed SteelConnect, IT teams can design, deploy, and manage new equipment from a central location. The network engineer simply designs a network in software and ships an SD-WAN gateway to a remote site. Once plugged in, it will automatically be discovered and brought online with Riverbed zero-touch provisioning.

Centralized control, support for multiple connections with different transports, dynamic path selection, and policy-based management using natural language further reduce the complexity of building and managing today's hybrid networks.

Our solutions addresses many scenarios

Service chaining amplifies SD-WAN benefits

Some SD-WAN solutions can be chained together with other network services. For example, WAN optimization (acceleration) can be combined with SD-WAN to improve network and application performance. Or Internet traffic leaving and entering a branch office may be routed across a VPN to a cloud-based security service to strike a balance between performance, security, and cost.

Riverbed SteelConnect SD-WAN is particularly strong in terms of services integration. It combines with SteelHead WAN acceleration as a tightly integrated solution to deliver optimal network performance. 

SteelConnect also sends data to SteelCentral Insights, which provides visibility into the usage and availability on the overall network, so you can monitor and troubleshoot performance issues as well as make informed policy and deployment decisions. 

Services integration goes beyond Riverbed. SteelConnect SD-WAN gives you single-click connectivity to the Zscaler cloud security platform. Many Riverbed products, including SteelConnect, expose powerful APIs to enable services chaining with other third-party solutions.

Cloud integration can't be an afterthought

The ever-increasing importance of the cloud in today's business environment is one of the main drivers of SD-WAN adoption, so an SD-WAN solution should be rich with features to ease the configuration and management of cloud-based services.

Again, this is another strength of the SteelConnect offering, which deeply integrates with both AWS and Microsoft Azure. Connecting branch offices to these public clouds via the Internet takes just a single click. The same is true for setting up private WAN via AWS Direct Connect and Microsoft Azure ExpressRoute. Riverbed even offers cloud-native SD-WAN gateways that run on AWS and Azure; just look in the relevant service's marketplace.

Ultimately, SteelConnect lets you build a centrally managed, unified fabric that connects clouds, data centers and branch offices. Policies written in the SteelConnect Manager console can be applied globally across clouds, data centers, WAN, and wired and wireless LAN to ensure consistency. You can also limit the scope of any policy to just one or a few sites. 

To us, this is what meaningful cloud support looks like.

Does SD-WAN make sense for you?

Given all that, is SD-WAN right for your organization? According to the Gartner Technology Insight for SD-WAN report:


  • SD-WAN should be included in future WAN architecture discussions. Specifically, organizations should look to SD-WAN if they are: 
  • Aggressively moving applications to the public cloud, such as Office 365 or Salesforce 
  • Seeking to reduce the operational complexity of their existing WAN 
  • Unhappy with the existing expense, performance and/or availability of their router-based WAN 
  • Negotiating an NSP WAN offering, such as MPLS and/or an MNS offering 
  • Refreshing WAN-edge devices, such as routers or WAN optimization controllers 
  • Supporting many small to midsize branch sites 
  • Embracing automation 
  • Moving toward a hybrid WAN topology 
  • Aggressively deploying video or other high-bandwidth, real-time applications to branch office locations 
  • Maintaining limited or no IT personnel on-site in remote branches”

Further resources

Going forward, Riverbed recommends that IT teams planning to upgrade their infrastructure should carefully consider incorporating SD-WAN into the roadmap, as its benefits cannot be ignored. Further, we believe that SD-WAN is now mature enough that organizations of any size can adopt the technology without experiencing outsized risk.

For more information about Riverbed's SD-WAN solutions, visit the What Is SD-WAN webpage and consult this helpful guide, How to Create an RFP for SD-WAN Solutions.

Gartner, Technology Insight for SD-WAN, 14 September 2018, Andrew Lerner, Jonathan Forest, Neil Rickard, Ted Corbett.