How to do it...

To learn about Shodan, follow the given steps:

1. Open your browser and visit https://www.shodan.io:

1. We begin by performing a simple search for the FTP services running. To do this we can use the following Shodan dorks: port:"21". The following screenshot shows the search results:

1. This search can be made more specific by specifying a particular country/organization: port:"21" country:"IN". The following screenshot shows the search results:

1. We can now see all the FTP servers running in India; we can also see the servers that allow anonymous login and the version of the FTP server they are running.
2. Next, we try the organization filter. It can be done by typing port:"21" country:"IN" org:"BSNL" as shown in the following screenshot: