Host anomalies from network data

Network administrators need to be able to quickly synthesize a large amount of raw data into comprehensive information and knowledge about a network system in order to determine if there is any unusual activity occurring on that network. This paper presents some initial results of a simplistic baselining method applied to a class B-sized network. These baselines are then used as the basis for an anomaly detection system that examines unusual amounts of activity to any one port on any one host. Thus we provide a system that can detect changes in the activity of any one host, regardless of whether those changes are noticeable when observing overall traffic behavior.