Network Flow Record (NetFlow)
Definition
A summarised record of a network conversation: source IP, destination IP, ports, protocol, byte count, and duration. Flow records do not contain payload content but establish communication patterns between hosts and are a primary evidence type in cyber investigations.
- Data captured
- Source/destination IP, ports, protocol, bytes, duration
- Content included
- No payload
- Use
- Establishes communication patterns between hosts
- Field
- Cyber forensics evidence
Common questions
How is a flow record used to identify data exfiltration?+
Unusually large or sustained outbound byte counts to an unfamiliar external IP can flag possible exfiltration even without any payload content being available.
Can flow records alone prove what data was transferred?+
No. They show that a conversation occurred and its volume, not its content, so correlating with other logs or a payload capture is needed to confirm what left the network.
Related terms
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