Security infrastructure
While a network security group provides a certain degree of network security on the switching and transport level of the OSI Reference Model, situations may arise in which you want to enable security for the higher levels of the stack.
In these situations, it is advisable to provide appliances provided by Azure partners for the security of virtual networks. These solutions are called Network Virtual Appliances (C).
NVA
Let's start with the question: What is an NVA? The answer consists of several parts as follows:
- An NVA is usually a third-party solution and is distributed over the Azure Marketplace
- An NVA is offered in the form of a VM
- An NVA is part of its own VNet subnet and stands apart from the rest of the VNet

Examples of using a NVA are:
- Firewall
- Intrusion detection/intrusion prevention
- Management of security risks
- Application control
- Network-based detection of anomalies
- Web filtering
- Virus protection
- Bot protection
One example of using an NVA in a VNet architecture, is to...