NEW YORK — As an early adopter of software-defined wide area networks (SD-WANs), retailer Gap has already replaced all the MPLS lines in their U.S. retail stores with dual-band Internet connections. Now the next big challenge is to extend that effort outside the U.S., and implement a hybrid SD-WAN strategy across offices around the world.

Speaking at the WAN Summit conference in New York, Shehal Patel, network architect for Gap, said the retailer is in the early stages of implementing a hybrid SD-WAN across all its offices in Asia using business-class Internet broadband connections that will be employed alongside an MPLS network.

At the same time, Gap is replacing MPLS connections at its retail stores to Europe, which will be followed by a similar rollout in Asia.

Patel says the goal is to deploy a fully routed secure network overlay that can be centrally managed and will provide access to more bandwidth than a 1.5 Mb/s T1 connection. After evaluating several options in 2014, Gap decided to standardize on the Secure Extensible Network (SEN) developed by Viptela to gain access to both border gateway protocol (BGP)  and option short path first (OSPF)  routing capabilities, Patel said.

That approach relies on a set of Viptela controllers deployed as a cloud service to manage local instances of a Viptela router that uses REST application programming interfaces (APIs) to communicate with the controllers. In total, Patel said Gap is trying to automate the creation and management of thousands of tunnels via the Viptela cloud service.

Another fundamental requirement, Patel said, is zero-touch provisioning. The operations teams need to be able to manage the SD-WAN on their own. “Operations needs to be able to manage the environment without having to bother the engineering team,” Patel said.

While both the retail stores and branch offices are making use of the same Viptela SEN platform, Patel noted that the network topology models are distinctly different. The retail stores are connected using a hub-and-spoke model because no retail stores are permitted to communicate with one another directly. In contrast, the remote offices are being connected using a mesh network architecture that routes most traffic through a central hub located in Tokyo.

In terms of SD-WAN advice, Patel said the most important thing is to make sure the operations teams tasked with managing the SD-WAN environment are trained early.

“The operation teams are not used to separating the control and data plane,” Patel said.