The SD-WAN Features Needed to Accelerate Global Application Delivery

August 29, 2018

SD-WANs are the go-to alternative for enterprises looking to reimagine their networks. With the right mix of SD-WAN features, IT can improve agility, availability, and, yes, even lower their network transport costs.

Where SD-WAN Falls Short

And yet for all of the good cheer promised by SD-WAN, anyone who’s tried to deliver a global network using the Internet must confront the problem of unpredictable SD-WAN performance. Traditional SD-WAN features focus on selecting the best path, not providing a better path.

Within test environments or regional networks, these limitations may not be apparent. But as distance grows, latency mounts. Add in the latency from the indirect paths Internet routing will select when sending packets, and it’s easy to see how latency will become too high for enterprise-grade communication. There are too few “good” routes available. And if no “good” paths exist through the network, there’s little an SD-WAN can do to compensate.

Which Tradeoff to Choose?

Few enterprises can risk sacrificing application performance and worker productivity in exchange for lowering their telecom costs. But what’s the alternative? You can play it safe by retaining a pricey MPLS circuit at each branch location and configuring your SD-WAN to route latency-sensitive traffic over it when Internet links are congested. That works but takes a big bite out of your cost-cutting efforts.

We believe there’s a better option: one that retains Internet economics while bumping up network characteristics to be on par with MPLS. The approach calls for a global, private backbone to eliminate the Internet’s performance issues across distance and instead rely on the Internet for what it does best: access.

SD-WAN as a Cloud Service

Cato Cloud, an SD-WAN as a service (SDWaaS). Cato Cloud is built on a global, affordable private backbone leased from multiple tier-1 IP service providers with SLA-backed capacity. And as a private backbone, the Cato Cloud network incorporates the key SD-WAN features needed to avoid the congestion, latency, and packet loss problems that plague the Internet. But a global backbone isn’t the only SD-WAN feature Cato Cloud provides for building a predictable, global network.

Key SD-WAN Features of Cato Cloud

  • Optimized traffic flows. We individually optimize traffic flows in the last mile (from customer location to PoP) and in the middle-mile (from PoP to PoP). Your traffic avoids Internet peering exchanges, where Internet providers hand off traffic to one another. So your traffic isn’t subjected to the congestion and sudden spikes in loss and latency that often occur in these locations.
  • Bandwidth management and control.  We run an encrypted software-defined overlay across all the backbone segments of our cloud infrastructure. The overlay uses application-aware routing and analyzes latency and loss statistics gathered from each backbone to select the optimum route, based on current network conditions. We also apply quality of service (QoS) capabilities, such as application and protocol priority marking, to ensure the performance of latency-sensitive, real-time applications.
  • Redundancy and failover. Like any Internet service, we take advantage of the redundancy inherent in the existing Internet infrastructure. Connecting our PoPs with multiple tier-1 IP backbones for diversity is one element of the redundancy built into Cato Cloud. PoP components can also take over for another in the event of a component failure. And if one PoP should become unreachable for any reason, we route traffic to another PoP.  

The result is an SD-WAN that can deliver the kind of availability and uptime typical of MPLS services but at a fraction of the cost. To learn more, read our blog about the impact of route diversity on SD-WANs.

Are Legacy SD-WANs ‘Good Enough?’

SD-WANs generally do a good job of choosing the best path to their destination, factoring in the application’s level of latency sensitivity and balancing those performance requirements against cost. But without a global, private backbone, an SD-WAN must depend on the Internet, and Internet performance remains unpredictable – especially over global distances. Your SD-WAN might be able to dynamically pick the least-congested path, but you’re out of luck if all the available paths happen to be congested.

Avoiding this either/or conundrum is the goal of Cato Cloud. It delivers Internet economics with MPLS reliability and performance. Budget-strapped enterprises no longer have to risk performance hits to meet their requirements. SD-WAN-as-a-service applies the private networking concepts inherent in MPLS to IP networks. To learn more, read our white paper, “The New WAN: Why the Private Internet Will Replace MPLS.”

Dave Greenfield

Dave Greenfield

Dave Greenfield is a veteran of IT industry. He’s spent more than 20 years as an award-winning journalist and independent technology consultant. Today, he serves as a secure networking evangelist for Cato Networks.