I. Focus on the fact that the primary purpose of an IDPS is to identify and report an intrusion.
II. Emphasize that IDPSs can provide triggers or clues of potential upcoming or hidden intrusions that would otherwise likely go unnoticed. This is through probing activities known as doorknob rattling or fingerprinting.
III. Recognize the fact that they can also protect assets even though systems are still exposed to known vulnerabilities or cannot respond quickly in a rapidly-changing environment.
IV. Relate to the fact that vulnerability-tracking groups are likely aware of vulnerabilities while the public may be shielded from the information.
V. Review the term zero-day vulnerabilities and why those are important to be aware of since they cannot be predicted or prepared for. Remember that most vulnerabilities become known when they are used in an attack.