Abstract-As the trend of successful network attacks continue to rise, better forms of intrusion detection and prevention are needed. This paper addresses network traffic visualization techniques that aid an administrator in recognizing attacks in real time. Our approach improves upon current techniques that lack effectiveness due to an overemphasis on flow, nodes, or assumed familiarity with the attack tool, causing either late reaction or missed detection. A port-based overview of network activity produces a improved representation for detecting and responding to malicious activity. We have found that presenting an overview using stacked histograms of aggregate port activity, combined with the ability to drill-down for finer details allows small, yet important details to be noticed and investigated without being obscured by large, usual traffic. Due to the amount of traffic as well as the range of possible port numbers and IP addresses, scaling techniques are necessary to help provide this overview. We provide graphs with examples of forensic findings. Finally, we describe our future plans for using live traffic in addition to our forensic visualization techniques.

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A computationally efficient method is presented for calculating field pressure distributions from a circular phased array transducer. This method employs a form of the rectangular radiator approach modified for use with the geometry of a circular array. The curved surface of the elements, radiating either continuous wave or pulsed excitation signals, is divided into incremental rectangular areas small enough so that the Fraunhofer approximation can be applied. Once the directivity of a single element is found, the array beam pattern can be calculated using superposition and suitable coordinate transformations. The validity of this approach is verified through comparisons with experimental data from a circular phased array. The results show that the location and amplitude of the grating lobes and main lobe width can be predicted with reasonable accuracy by using this method.

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