Nmap has been written and is maintained by “Fyodor” as the greatest security utility and an extremely powerful tool.
The objective of this paper is to report about Nmap (network mapper) and covers in essence, information about scanning techniques. It starts of the discussion by describing the meaning of the network scanning as a process to establish active hosts on a network and follows on to cover port scanning which is a technique for attackers to discover exploitable communication channels that they can use to break into systems. Thereon, the report moves on to provide a description of Nmap, an intelligent device for checking the accuracy of the scanned data. The Port Scanning Basics are then divided into six states and discussed. Thereon the Each technique is focused upon to solve a specific problem. The Nmap TCP Maimon scan and the Nmap TCP ACK scan have the main emphasis in this report and are described in significant detail.
The concept of the network scanning is that it is a process to establish active hosts on a network for the objectives of network security assessment or attacking them. Scanning processes such as port scans and ping sweeps return details which the respective IP addresses map to the live host that is active on the internet and what use this address offers. Another scanning tactic is the Inverse Mapping which returns information to show which IP addresses do not map to live host thereby allowing an attacker to make assumptions about viable addresses. Scanning is one of three constituents of intelligence gathering for an attacker, and it provides him/her with the information necessary to enable him/her to apply the very large spectrum of attack techniques. The attacker can make a profile of the goal organization with some information such as the domain name system and an E-mail server, and its IP address scope. Usually the information is available online and consequently, the attacker can find .details about the IP address which it decides to access over the internet through its operating system, etc.