SiLK (System for Internet-Level Knowledge) consists of two sets of tools: a packing system and an analysis suite. The packing system receives Netflow V5 PDUs and converts them into a more space efficient format, recording the packed records into service-specific binary flat files. The analysis suite consists of tools that can read these flat files and then perform various query operations, ranging from per-record filtering to statistical analysis of groups of records. The analysis tools interoperate using pipes, allowing a user to develop a relatively sophisticated query from a simple beginning.
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