Implementing network protection in Azure
This section will look at the network protection options available in Azure. This will cover NSGs, application security groups (ASGs), and the Azure Firewall; we will look at the use cases, how they work, and their capabilities.
This section will look at NSGs as the first skill area.
NSGs
An NSG is a packet filter approach controlling traffic flow into and out of resources such as VMs.
A set of inbound and outbound rules filters network traffic, denying all traffic unless explicitly allowed.
An NSG evaluates whether access is allowed or denied based on five data points (the 5-tuple method); these data points are as follows:
- Source
- Source port
- Destination
- Destination port
- Protocol
NSGs are represented in the following diagram:
Figure 6.13 – NSGs
NSGs can be associated with a network interface or a subnet, but not a VNet. A subnet or network interface can only have one...