Passive discovery is the identification of devices and services by observing network traffic or telemetry without directly probing the systems. It matters because some environments need visibility methods that avoid the risk of disrupting fragile or sensitive systems.
What is Passive Discovery?
Passive approaches use mirrored traffic, flow data, logs, or monitoring feeds to infer what systems exist and how they behave. They are especially valuable in OT, legacy, or operationally sensitive networks.
What Passive Discovery Commonly Supports
Common uses include asset visibility, OT discovery, low-impact monitoring, traffic analysis, and supplemental inventory improvement.
Passive Discovery vs. Active Scanning
Passive discovery observes traffic already happening. Active scanning sends direct queries or probes to elicit responses from systems.
Frequently Asked Questions
Why use passive discovery?
Because it reduces the chance of disrupting sensitive systems while still building visibility.
Does passive discovery find everything?
Not always. Quiet or rarely active systems may remain less visible than they would under active probing.
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