Breaking Down the Real Meaning of an XDR Solution
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Learn how Fidelis Deep session Inspection improves visibility, threat detection, and contextual
When it comes to network analysis and security, metadata, PCAP, and NetFlow each serve critical yet distinct roles. Metadata captures essential communication details—source and destination IPs, ports, protocols, session durations—providing lightweight, real-time visibility. PCAP records complete packets (headers plus payloads), enabling deep packet inspection and forensic reconstruction. NetFlow sits in between: it aggregates flow records from network devices, summarizing conversation characteristics such as start and end times, byte and packet counts, protocol usage, and interface information.
In this article, we’ll explore each technology in depth, compare their strengths and limitations, and provide best practices for integrating all three into a unified network security strategy.
Network metadata consists of high-level summaries of all network communications. Each metadata record includes attributes such as:
Because metadata omits payload content, it remains lightweight—typically under 100 bytes per record—enabling continuous, real-time ingestion into SIEMs, NDR platforms, or cloud-based analytics. Organizations leverage metadata for 24×7 monitoring, automated anomaly detection playbooks, and historical trend analysis over months or years without prohibitive storage costs.
Packet Capture (PCAP) is the process of intercepting and recording every bit of data transmitted across a network interface. A PCAP file includes:
PCAP tools—such as Wireshark, tcpdump, and specialized network taps—offer unparalleled visibility into protocol-level interactions and payload contents. This depth is indispensable for:
However, raw PCAP data is voluminous. A single gigabit link can generate over 100 GB of PCAP per day, demanding significant compute and storage resources, and typically retained only for short windows (days to weeks).
NetFlow, originally developed by Cisco, captures metadata at the flow level—essentially grouping packets that share common attributes into a single flow record. Key components of a NetFlow record include:
Unlike raw PCAP, NetFlow does not retain packet payloads, but it provides richer context than basic metadata by summarizing entire conversations. Typical flow record sizes range from 100 to 200 bytes, making it scalable for enterprise and service-provider environments. NetFlow excels in:
Modern variants—such as IPFIX or Juniper’s J-Flow—extend NetFlow to include application-level classification, URL tags, and rich VLAN metadata, further closing the gap to PCAP-level insights without the payload overhead.
Below is an in-depth, side by side comparison of the three technologies across critical dimensions:
| Category | Metadata | NetFlow | PCAP |
|---|---|---|---|
| Data Granularity & Detail |
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| Storage Requirements |
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| Analysis Complexity |
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| Real Time Detection |
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| Forensic & Investigation |
| Flow timelines identify windows of interest quickly | Full packet reconstruction reconstructs attacker tools and data exfiltration |
| Encrypted Traffic Insight | Analyzes traffic volumes, timings, and patterns without decryption | Monitors flow sizes, packet inter-arrival times to infer encrypted tunnels | Cannot decipher encrypted payloads unless decrypted externally |
| Scalability & Performance | Minimal CPU/memory footprint; suited for distributed sensors | Moderate resource use; often implemented in routers or probes | High-performance appliances required; centralized data collection |
| Integration & Automation | Native SIEM/XDR integration; drives SOAR playbooks | Feeds flow analyzers and SIEM; supports automated threshold-based alerts | Ingested post-capture into specialized forensic or DPI platforms |
Dive Into Metadata: Reveal the secrets hidden in your—and the next actions to take.
| Use Case | Metadata | NetFlow | PCAP |
|---|---|---|---|
| Real-Time Monitoring |
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| Anomaly Detection |
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| Scalability & Storage |
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| Forensic Investigation |
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| Detailed Traffic Inspection |
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| Encrypted Traffic Analysis | Analyzes patterns, volumes, and timing without decryption | Infers encrypted tunnels through flow size and timing anomalies | Cannot inspect encrypted payloads without decryption keys or proxies |
| Cost & Performance |
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| Integration & Automation | Native integration with SIEM/XDR and SOAR playbooks |
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Combining metadata, NetFlow, and PCAP creates a layered approach to network defense. Each data type brings unique strengths:
Together, they enable:
Fidelis Network® Detection and Response (NDR) provides extensive visibility and advanced threat detection by analyzing rich metadata, NetFlow data, and packet captures (PCAP). This integrated approach enables security teams to detect, investigate, and respond to threats effectively.
Fidelis Network captures and analyzes over 300 metadata attributes per session, offering deep insights into network activities. This rich metadata includes details such as IP addresses, ports, protocols, timestamps, and session durations, facilitating:
Fidelis NDR analyzes flow data (e.g., NetFlow, IPFIX) from all network devices, providing visibility into network traffic patterns. This includes monitoring encrypted traffic using metadata analysis and session behavior profiling, which supports:
Fidelis NDR includes features for capturing and analyzing packet-level data, which is essential for:
Fidelis NDR leverages supervised and unsupervised machine learning to establish baselines of normal network behavior, enabling the system to:
By integrating metadata, NetFlow, and PCAP data, Fidelis NDR offers a cohesive platform for:
See why security teams trust Fidelis to:
Network metadata, which includes details like IP addresses and session lengths, is crucial for understanding network communications and enhancing security. It facilitates effective monitoring and aids in proactive threat detection.
Packet capture (PCAP) provides a comprehensive view of network traffic by capturing entire packets, including headers and payloads, while network metadata offers a summarized view that omits full packet content for efficient real-time analysis. This distinction highlights PCAP’s detailed approach compared to the storage-friendly nature of metadata.
Network metadata plays a crucial role in real-time network monitoring, anomaly detection, and behavioral analysis, enabling the identification of potential security threats through pattern analysis of network activity. This immediate insight into network performance enhances overall security measures.
See Fidelis in action. Learn how our fast and scalable platforms provide full visibility, deep insights, and rapid response to help security teams across the World protect, detect, respond, and neutralize advanced cyber adversaries.