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 system, typically conducting a port scan to determine find any open ports.
What is network reconnaissance?
Network reconnaissance is a term for testing for potential vulnerabilities in a computer network. This may be a legitimate activity by the network
owner/operator, seeking to protect it or to enforce its acceptable use
policy. It also may be a precursor to external attacks on the network.