The most important requirement when collecting admissible evidence is the chain of custody. The chain of custody is a documented record of who had control of the evidence at any given time, from the point of collection until the evidence is presented in court. This is important in order to ensure the evidence can be authenticated and is not subject to tampering or any other form of interference. Other important considerations include need to know, preserving audit logs, and due diligence.

During post-incident reviews, the highest priority should be given to evaluating the effectiveness of the incident response effort. This includes assessing the accuracy of the response to the incident, the timeliness of the response, and the efficiency of the response. It is important to assess the effectiveness of the response in order to identify areas for improvement and ensure that future responses can be more effective. Documenting the actions taken in sufficient detail, updating key risk indicators (KRIs), and evaluating the performance of incident response team members are all important components of a post-incident review, but evaluating incident response effectiveness should be given the highest priority.

An anomaly-based intrusion detection system (IDS) operates by gathering data on normal network behavior and using it as a baseline for measuring abnormal activity. This is important because it allows the IDS to detect any activity that is outside of the normal range of usage for the network, which can help to identify potential malicious activity or security threats. Additionally, the IDS will monitor for any changes in the baseline behavior and alert the administrator if any irregularities are detected. By contrast, signature-based IDSs operate by gathering attack pattern signatures from historical data and comparing them against incoming traffic in order to identify malicious activity.