Slide 24
Slide 24 text
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Feature-Based Anomaly Detection
Categorical Features *
• Categorical Features - can take on one of a limited, and usually fixed, number of possible values
• Stream Sketch - algorithm produces an approximate answer based on a summary of the data stream in memory
Example: Protocol {UDP|FTP|HTTP|…}, GEO-MET {PHOENIX | DALLAS | LONDON| …}, …
Count-Min (CM) Sketch : number of occurrences of the element in a stream (Heavy Hitters)
Why not count? Protocol: 42k elements per asset. GeoMet: 246k per asset
Time Series DB
Categorical Data
CM
Sketch Heavy Hitters
Asset Bin Value
Server 1 15 HH
Server 2 15 HH
Server (N) 15 HH
MR
Table Name: Protocol
Unstructured Data
CM
Sketch Alert
Expected: {HTTP, UDP, FTP, DNS}
ACTUAL: {DNS, ICMP, HTP, FTP}