I think infrastructure testing is comprised of everything, hardware, software, servers, the aplication, all these components which make up the infrastructure, while application is just what we normally do and concentrate on particular software app.
Response time is more of a test objective rather than a type of test. There are different types of tests, like component testing, load testing, stress testing and volume testing.
Check around online, there are plenty of resources for this.
Regards,
Mario M.
