In port mirroring, data must be collected in which manner for reliability?

Port mirroring, also known as SPAN (Switch Port Analyzer), is a technique used to monitor network traffic. In the context of reliability, data must be collected in real time to ensure that every packet of interest is captured without delays or losses.

Real-time data collection allows network administrators and security analysts to continuously monitor and analyze the communication happening over the network. This is crucial for tasks such as troubleshooting, performance tuning, and identifying security threats, as it provides an accurate and up-to-date view of traffic patterns and issues as they occur. By capturing data in real time, any anomalies or performance issues can be addressed immediately, reducing the risk of missed critical events or reactive measures when issues escalate.

Other methods such as collecting data in intervals or asynchronously can introduce a lag in the information available, which can lead to incomplete monitoring and an inability to respond swiftly to potential problems. Using a compressed format might conserve bandwidth but could obscure important details necessary for accurate analysis. Thus, real-time collection stands out as the most reliable approach in port mirroring for maintaining comprehensive and timely oversight of network activity.