Footprinting is nothing but accumulating and revealing as much as data about the target network before gaining access into any network.
Open Source Footprinting: It will search for the contact data of administrators that will be utilized for guessing password in Social Engineering
Network Enumeration: The hacker attempts to distinguish the domain names and the network blocks of the target network
Scanning: After the network is known, the second step is to spy the active IP addresses on the network. For distinguishing active IP addresses (ICMP) Internet Control Message Protocol is a functioning IP addresses
Stack Fingerprinting: the final stage of foot printing step can be performed, once the hosts and port have been mapped by examining the network, this is called Stack fingerprinting.