The tools included in this category are used to identify the target machines that can be accessed by a penetration tester. Before we start the identification process, we need to know our client's terms and agreements. If the agreements require us to hide penetration-testing activities, we need to conceal our activities. Stealth techniques may also be applied for testing the Intrusion Detection System (IDS) or Intrusion Prevention System (IPS) functionality. If there are no such requirements, we may not need to conceal our penetration-testing activities.