NSG (Network Security Group) – Azure’s network traffic filter.
Azure Network Security Groups provide traffic filtering capabilities for resources in Azure virtual networks. They contain security rules that allow or deny inbound/outbound traffic based on source/destination, port, and protocol. NSGs can be associated with subnets or individual network interfaces, support service tags for simplified management, and include default security rules. The service features priority-based rule processing, augmented security rules for complex scenarios, and diagnostic logging through Azure Monitor.
