An Overview of Remote Operating System Fingerprinting

Operating System (OS) fingerprinting is the science of determining the operating system of a remote computer on the Internet. This may be accomplished passively by sniffing network packets traveling between hosts, actively by sending carefully crafted packets to the target machine and analyzing the response, or through non-technical means. It is used by Security Professionals (known as 'White-hats') and Hackers ('Black-hats') alike for mapping remote networks and determining which vulnerabilities might be present to exploit. This paper presents an overview of the various approaches to OS fingerprinting some current tools available on the Internet together with their features the underlying techniques they use and suggestions for defeating these tools.