If things work out the way proponents hope, software-defined WANs will make tying corporate locations together far more efficient, increase functionality and reduce costs. SD-WANs are an implementation of software-defined networks. Today, network elements are purpose-built physical devices. If a company wants a firewall to protect an office, it calls a service provider or carrier who sends out a guy – it always was a guy – with a firewall in a truck. He deploys it into the network ...