Sams Teach Yourself TCP/IP in 24 Hours, Third Edition

Attacking a Network

A network attack is often an elaborate and methodical operation. A hacker sometimes spends days or weeks scouting and mapping the system so he'll know exactly how the network is organized. The reconnaissance process typically consists of the following:

• Gathering information— A full-scale network attack begins with a broad sweep to determine as much information as possible about the company. This process is sometimes called footprinting. Some of this information can be collected over the Web: company locations, email addresses, and affiliations, as well as links to other Web sites. The intruder attempts to obtain any and all domain names used by the company. The domain names are then used to query DNS servers for company IP ...