Passive Reconnaissance

Passive Reconnaissance is the process of collection information about the target system, network or organization/company. You do not directly interact with any of their resources or alert the target you are looking into them.  The reason you do passive reconnaissance is to gather information and gain a better understanding of the targets infrastructure, possible vulnerabilities, business relationships and other valuable information that you can use later. Keep in mind that this should be done ethically and within all legal bounds.