OS detection technique with Nmap

Before we talk about remote operating system detection, let's discuss what Nmap is and what it can do. I will also walk you through different flags and nobs that can be used with the Nmap tool in general.

Nmap tool

Network Mapper (Nmap) is a freely available open source tool for systems and network administrators, allowing them to perform tasks such as collecting enterprise network inventory, managing service upgrade schedules, basic security audits, and monitoring hosts or service up-time. Nmap is officially available for major computer operating system platforms such as Linux, Windows and macOS X.

Nmap binaries can be downloaded from https://nmap.org/download.html. After successful installation, you can check the version simply by passing the nmap -V command: 

• Windows: Output on Windows shows that the program currently installed is Nmap version 7.60:

• Linux: Output on Linux shows that the program currently installed here is Nmap version 6.40:

Nmap can be run using...