SiLK: "SiLK, the System for Internet-Level Knowledge, is a collection of traffic analysis tools developed by the CERT Network Situational Awareness Team (CERT/NetSA) to facilitate security analysis of large networks. The SiLK tool suite supports the efficient collection, storage and analysis of network flow data, enabling network security analysts to rapidly query large historical traffic data sets. SiLK is ideally suited for analyzing traffic on the backbone or border of a large, distributed enterprise or mid-sized ISP.

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