Abstract: The present invention concerns a method and a system for measuring the thermal diffusivity. Said method comprises the steps of: subjecting a surface region of an object to a modulated heating beam (3) while providing a signal (MLS) thereof, the heated spot or area (4) of the surface of the sample (2) having a definitive diameter and a fixed intensity distribution profile; providing a signal (MTS) proportional to the temperature of the heated spot area (4); determining the phase difference between the modulated beam signal (MLS) and the resulting modulated temperature signal (MTS); and using said determined phase difference and the associated frequency to work out the thermal diffusivity value of said object (2).

Abstract: The method and apparatus of the present invention provide real time detection of abnormal data streams in high bandwidth data pipes, such as those found at network service provider data hubs. Abnormally high data volumes, for example, those associated with Denial of Service [DOS] attacks, may be detected and a mitigating response to the attack initiated. Further, certain counterattack steps are instituted including reverse tracing to determine the source of the attack and attack signature recording for later comparison to suspected new attacks. The method and apparatus of the present invention are such that the entire volume of data passing through a high bandwidth data pipe may be monitored on a real time basis providing early warning of DOS attacks for very large network address spaces.

Abstract: The present invention concerns a method and a system for measuring the thermal diffusivity. Said method comprises the steps of: subjecting a surface region of an object to a modulated heating beam (3) while providing a signal (MLS) thereof, the heated spot or area (4) of the surface of the sample (2) having a definitive diameter and a fixed intensity distribution profile; providing a signal (MTS) proportional to the temperature of the heated spot area (4); determining the phase difference between the modulated beam signal (MLS) and the resulting modulated temperature signal (MTS); using said determined phase difference and the associated frequency to work out the thermal diffusivity value of said object (2).