Abstract: A method for detecting abnormal network data includes performing feature extraction on a network data packet according to each of plural protocol types, and generating a corresponding data packet fingerprint set. The data packet fingerprint set includes one or more data packet fingerprints, each of the one or more data packet fingerprints corresponding to one of the plural protocol types. The method further includes matching at least one data packet fingerprint in the data packet fingerprint set and a reference data packet fingerprint in a reference data packet fingerprint library, and calculating a confidence corresponding to the network data packet based on confidence correlation information corresponding to each of the at least one matched data packet fingerprint. The method also includes obtaining a reference confidence, and determining an abnormality detection result of the network data packet based on the reference confidence and the calculated confidence.

Abstract: A method for detecting abnormal network data includes performing feature extraction on a network data packet according to each of plural protocol types, and generating a corresponding data packet fingerprint set. The data packet fingerprint set includes one or more data packet fingerprints, each of the one or more data packet fingerprints corresponding to one of the plural protocol types. The method further includes matching at least one data packet fingerprint in the data packet fingerprint set and a reference data packet fingerprint in a reference data packet fingerprint library, and calculating a confidence corresponding to the network data packet based on confidence correlation information corresponding to each of the at least one matched data packet fingerprint. The method also includes obtaining a reference confidence, and determining an abnormality detection result of the network data packet based on the reference confidence and the calculated confidence.

Abstract: The present invention provides an optical head with a single or multiple sub-wavelength light beams, which can be used in arenas such as photolithography, optical storage, optical microscopy, to name a few. The present invention includes a transparent substrate, a thin film, and a surface structure with sub-wavelength surface profile. The incident light transmits through the transparent substrate, forms a surface plasma wave along the sub-wavelength aperture located within the thin film, and finally re-emits through spatial coupling with the sub-wavelength profile of the surface structure. As the coupled re-emitting light beam or light beams can maintain the waist less than that of the diffraction limit for a few micrometers out of the surface with sub-wavelength profile in many cases, this invention can have applications ranging from micro or nano manufacturing, metrology, and manipulation by using light beams with waist smaller than the diffraction limit.