Final answer:
To control the ports that devices on the internet can use to access VMs, Network Security Group (NSG) rules and Azure Firewall rules are commonly used. NSG rules can filter traffic based on port and IP addresses, while Azure Firewall manages and logs network policies.
Step-by-step explanation:
To control the ports that devices on the internet can use to access Virtual Machines (VMs), you can use several methods. One common solution is implementing Network Security Group (NSG) rules. These are used in cloud platforms, like Microsoft Azure, to filter network traffic to and from Azure resources. NSG rules can allow or deny traffic based on factors such as port, protocol, source IP address range, and destination IP address range.
An alternative is using Azure Firewall rules. Azure Firewall is a managed, cloud-based network security service that protects your Azure Virtual Network resources. It allows you to create, enforce, and log application and network connectivity policies across subscriptions and virtual networks.
While subnet configurations and VPN configurations play a role in network architecture and secure connectivity, respectively, they do not directly control port access in the same way NSG or firewall rules do.