Answers

1. We create an input adapter when we need to expose software features to be accessed by driving actors. These actors can access the hexagonal application using different technologies or protocols, such as HTTP REST or via the command line.
2. The main benefit is that the same logic, contained in an input port, can be used to treat data that comes from different input adapters.
3. Output adapters must always implement output ports. By doing that, we are sure that the adapters are in line with the requirements expressed by the domain model.
4. They are both from the Framework hexagon.