INTRODUCTION In the previous walkthrough, we put together a basic environment, creating a resource group, a VNet, a VM, and a storage account just enough infrastructure to have something real to manage. This time we're going back into that network and giving it some actual structure: a dedicated subnet for SFTP (Secure File Transfer Protocol) traffic, plus a network security group to control exactly what's allowed in and out of it. If you haven't built the base environment yet, it's worth...