How your service assurance strategy can improve

the economics for SD-WAN

sd wan

If you have been to any industry conference for Service Providers or Network Operators recently, you could not have missed the buzz around SD-WAN (Software-Defined Wide-Area Networking). It has seemingly popped up out of nowhere and become all the rage. While it is relatively new in the service provider lexicon, it is actually a fairly mature technology amongst enterprise customers with distributed locations.

SD-WAN was developed as a cost-effective alternative for site-to-site connectivity and redundancy between distributed branch offices or branch offices and a data center. Traditionally, organizations would leverage a main WAN connection with an MPLS backup. All in the interest of distributing traffic over the wide-area network while maintaining path redundancy.

Unfortunately, such a solution was expensive, it took a considerable amount of time to provision and install, and it lacked the flexibility and agility enterprise customers are requesting. With the rise of broadband access, a broadband connection quickly became a lower-cost, faster-to-provision method for connectivity. SD-WAN became a software overlay to the broadband connection that allowed for better network grooming, diverse routing, all at a fraction of the cost of earlier alternatives.

While it is attractive for enterprise customers to pursue SD-WAN, for some carriers, it is viewed skeptically as it comes at a loss of revenue from MPLS, Metro Ethernet, and other expensive options as they are decommissioned or no longer being considered. Fortunately, this story has a silver lining for service providers.

For service providers, operating the SD-WAN has significant advantages. First, it provides greater insight, flexibility and control over the access network. Second, it opens up new revenue opportunities. Lastly, it can and will have the ability to significantly reduce the cost of field maintenance because network operations teams will be better able to assess problems from the premises to the access to core network.


To understand the benefits of SD-WAN, it is important to understand a little more about SD-WAN. SD-WAN requires either a universal CPE (uCPE) device or an appliance at each branch location and a centralized broadband gateway (BGW) or SD-WAN controller. For an operator, the BGW or SD-WAN controller would reside in the network and enforce policy amongst the uCPE/appliance devices.

While many operators see the advantage of greater visibility and control of the WAN, it is with the premise view that operators can unlock tremendous value from the technology and their service assurance strategy. Using a uCPE, a white box platform, the operator has the ability and flexibility to instantiate virtual services on the device.

As part of service assurance strategy, two key virtual services would be:

1. The ability to “see” or monitor the performance of these virtual services

2. The ability to generate synthetic transaction to send across the WAN.

These two simple virtual functions hold a game changing capability for network operators because, for the first time, it allows the operator to remotely understand the health of the WAN (from SD-WAN) AND the health of the premise applications via probing and synthetic transactions and the ability to generate packets before the WAN and measure after the WAN for errors, throughput, etc.

This ability to have purview into the premise now allows a remote, network operation to diagnose problem and communicate with customer or field maintenance teams who exactly owns the problem and the exact nature of the problem. With the cost of a truck roll exceeding $100, even a nominal reduction in truck rolls can represent a significant savings to the network operator.

As operators pursue SD-WAN offerings, it is imperative that it be viewed in context of their service assurance strategy. By doing so, operators will be able to reap the benefits, insight, and coordination with their existing service assurance infrastructure and both increase service reliability while driving down operational costs.

~Written by Mike Serrano, Sr. Product Marketing Manager, NETSCOUT