Tectonic shifts in application and traffic patterns are leaving no portion of the network unchanged. What started as network virtualization in the data center has spilled into other portions of the network with the Wide Area Network (WAN) becoming a poster child for this transformation.

Large carriers are viewing this evolution opportunistically -- and as much more than a simple transition from MPLS to Broadband Internet. Instead, Software Defined WAN (SD-WAN) represents a new revenue generation technology for them. Here's why:

To deliver end-to-end services to enterprises, carriers typically use their own circuits and infrastructure relying on peering arrangements with other providers. These third-party circuits eat into profit margins. With SD-WAN, carriers can use the most profitable underlying circuit technology available -- third-party MPLS circuits, broadband Internet or even LTE/4G -- to deliver WAN services to businesses.

Service-level agreements (SLAs) are typically based on network-based metrics: loss, latency and jitter. With SD-WAN, carriers can offer application-based SLAs. That’s because SD-WAN provides application level visibility needed to monitor network level SLAs based on the paths taken by an application and make proactive changes to the network in anticipation of a problem.

MPLS has traditionally been considered secure because it provides isolation. With SD-WAN, carriers can upsell customers multiple layer-3 VPNs (for segmentation) that provide both isolation and end-to-end network encryption. Integrated security and segmentation is becoming a requirement into many sectors such as financial services and healthcare.

Most carriers have deployed complex OSS/BSS systems that are stitched together using a combination of homegrown and vendor provided alerting and management technologies. SD-WAN provides rich APIs that carriers can use to manage the network centrally. This allows for zero touch provisioning that enhances the customer service experience, while dramatically improving profitability by avoiding truck-rolls. These centralized management and operational control capabilities make it possible to bring up, upgrade or provision hundreds or thousands of devices in a customer’s network at a click of a button on a GUI. Day-one and day-two operations become extremely streamlined.

Typically customer sites are littered with hardware devices -- routers, firewalls, optimizers and other appliances for L4-L7 services. They provide revenue for network equipment vendors. Using Network Functions Virtualization (NFV), carriers can consolidate these devices/services and shift revenue dollars from hardware to software -- and keep a larger percentage of the end-to-end service profits. SD-WAN provides the connectivity glue that transports customer traffic from individual sites to intermediate NFV service end-points before it reaches its final destination. It even enables carriers to enforce policies that can inspect and drop traffic that matches preset criteria.

Ultimately, the biggest advantage that SD-WAN provides carriers is end-to-end control over services to the customer premises. This newfound agility means carriers can complete service requests in one day instead of weeks, and help customers bring up their sites in days instead of months. That’s what is driving carriers towards SD-WAN.

— Ramesh Prabagaran, vice president of product management, Viptela