Nmap is a network scanner created by Gordon Lyon. Nmap is used to discover hosts and services on a computer network by sending packets and analyzing the response. In this task you will further explore your understanding and use of Nmap. Nmap provides several features for probing computer networks, including hosts discovery and service and operating systems, vulnerability detection, and other features. Nmap can adapt to network conditions including latency and congestion during scan. In this task, you will focus mainly on port scanning, OS detection, and using scripts for vulnerability detection. You need to set up your test environment so that you have a host machine to initiate the scanning and one or more targets as required. You can set up your test environment with different virtual machines (kali Linux, MAC OS, windows 8.1, Metasploitable etc) running in VirtualBox and complete the following tasks.

a) First, use the Nmap to show the running port in the target machine. Then, start / stop at least three ports in the target machine and run the port scan again to show the difference.