The Network Situational Awareness (NetSA) group at CERT has developed and maintains a suite of open source tools for monitoring large-scale networks using flow data. These tools have grown out of the work of the AirCERT project, the SiLK project and the effort to integrate this work into a unified, standards-compliant flow collection and analysis platform.

If you are new to the NetSA Security Suite, start with this overview of the components that comprise the NetSA Security Suite and their inter-operation.

CERT is a part of the Software Engineering Institute (SEI), a federally funded research and development center (FFRDC) operated by Carnegie Mellon University.

Featured Projects

Mothra 1.6.0

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Mothra is a collection of libraries and tools for working with network flow data in the Apache Spark large-scale data analytics engine.

SiLK 3.23.1

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The System for Internet Level Knowledge (SiLK) is an efficient network flow collection and storage infrastructure that will accept flow data from a variety of sensors. SiLK also provides a suite of efficient command-line tools for analysis.

YAF 2.16.1

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Yet Another Flow Sensor (YAF) processes packet data into bidirectional flow records that can be used as input to an IPFIX Collecting Process. YAF's output can be used with Super Mediator, Analysis Pipeline 5, Mothra, and the SiLK Tools.

Analysis Pipeline 5.11.4

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The Analysis Pipeline 5.11 is a streaming analysis tool than can process more than just SiLK flows as done in version 4.x. It can now process YAF records and raw IPFIX records. It can do all of the analyses available in version 4.x. A notable enhancement is expansive DNS record processing. This includes fast flux detection and domain name watchlisting.

super_mediator 1.11.0

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super_mediator is an IPFIX mediator for use with the YAF and SiLK tools. It collects and filters YAF output data to various IPFIX collecting processes, JSON files, and/or csv files. super_mediator can be configured to perform de-duplication of DNS resource records and TLS records as exported by YAF.