Networking and security are often treated as adjacent concerns, but in a cloud-native architecture, they are inseparable. In Azure, the boundaries of your network define your security posture. Every virtual machine, container, storage account, and application endpoint you deploy lives within a virtual network, an abstraction that replaces the traditional firewall and switchboards of on-premises data centers. But while Azure’s networking model simplifies many physical constraints, it introduces new layers of abstraction and complexity. Subnets are no longer just IP ranges; they are security domains. Firewalls are programmable. Routing tables are dynamic. And with the rise of hybrid and multicloud deployments, network perimeters have become porous and context-driven.