Network Forensics
Network forensics is the capture, recording, and analysis of network traffic and events to detect security incidents, investigate breaches, gather evidence, and understand attacker behavior within a network environment.
Network forensics is a specialized discipline within digital forensics that focuses on monitoring and analyzing network communications. It plays a vital role in incident response by helping security teams reconstruct attack timelines, identify compromised systems, determine data exfiltration scope, and gather evidence for legal proceedings. Network forensics operates on the principle that all network activity leaves traces that can be captured and analyzed.
Key techniques include full packet capture, which records complete network traffic for later analysis; flow analysis, which examines metadata about network connections; and log correlation, which combines data from multiple sources like firewalls, IDS, and DNS servers. Tools commonly used include Wireshark, tcpdump, Zeek (formerly Bro), NetworkMiner, and commercial network detection and response platforms.
Effective network forensics requires strategic deployment of capture points, sufficient storage for packet data, proper time synchronization across all devices, and well-defined procedures for evidence handling and chain of custody. Organizations should implement continuous network monitoring, retain traffic logs according to policy requirements, train analysts in traffic analysis techniques, and integrate network forensics capabilities with their overall incident response plan. The growing use of encryption presents challenges that may require TLS inspection at network boundaries.