The process of collecting information about an intended target of a malicious hack by probing the target system. Active reconnaissance typically involves port scanning in order to find weaknesses in the target system (i.e., which ports are left vulnerable and/or if there are ways around the firewall and routers). What is footprinting and reconnaissance? Footprinting (also known as reconnaissance ) is the technique used for gathering information about computer systems and the entities they belong to. To get this information, a hacker might use various tools and technologies. This information is very useful to a hacker who is trying to crack a whole system. What is passive reconnaissance? Passive reconnaissance is an attempt to gain information about targeted computers and networks without actively engaging with the systems. In active reconnaissance , in contrast, the attacker engages with the target sys...